Siren

Siren (pronounced sahy-ruhn)

(1) In classical mythology, one of several sea nymphs, sometimes depicted as part-woman, part-bird (and sometimes as sisters) who, with their seductive singing (their “siren song” or “siren call”), lured mariners to destruction on the rocky shore.

(2) A woman who sings sweetly and charms.

(3) In slang, a seductively beautiful or charming woman, especially one who beguiles men; a seductress, temptress or vamp; a dangerous woman who preys on the weaknesses and susceptibilities (there are a few of both).

(4) An acoustical instrument for producing musical tones, consisting essentially of a disk pierced with holes arranged equidistantly in a circle, rotated over a jet or stream of compressed air, steam or the like, so that the stream is alternately interrupted and allowed to pass.

(5) An variation of this implement, making a piercingly loud sound and used as a whistle, fog signal, or warning device; the sound made by such a device.

(6) In zoology, (1) any of several aquatic, eel-like salamanders of the family Sirenidae, having permanent external gills, small forelimbs and no posterior limbs, (2) a member of Sirenia, an order of mammals or (3) any of various nymphalid butterflies of the genus Hestina.

(7) Anything seductive or tempting (especially if potentially dangerous or harmful (something said to exert “a siren call” on one’s desire).

(8) In music, a musical instrument (one of the few aerophones in the percussion section of the symphony orchestra).

(9) An instrument for demonstrating the laws of beats and combination tones.

(10) In astronomy & astrophysics, an astrophysical event able to be used for calculating cosmic distances.

(11) As “siren suit”, an overall-like one-piece garment introduced in the UK during the “Blitz” as something to be worn by those in air-raid shelters.  

1300-1350: From the Middle English siren & serein, from the Old French sereine, (the Modern French sereine dating from the twelfth century), from the Late Latin sīrēna and the Classical Latin Sīrēn & Sīrēna, from the Ancient Greek Σειρήν (Seirḗn).  The Seirēnes were the alluring sea nymphs of classical mythology and the figurative sense of “one who sings sweetly and charms” was first noted in the 1580s although the classical descriptions of them were mangled in medieval translations, resulting in some odd and fantastical notions of their appearance and it wasn’t unusual for them to be conflated with mermaids.  The Vulgate (the Biblia Vulgata, the fourth century translation of the Bible which, through the choices of words and senses made by the translator(s) had a profound effect on Christianity and Christendom) also gifted to Middle English the use of the word to describe an imaginary species of flying serpents, based on glossary explanations of the Latin sirenes in Isaiah 13:22 (“And the wild beasts of the islands shall cry in their desolate houses, and dragons in their pleasant palaces: and her time is near to come, and her days shall not be prolonged.”  (King James Version of the Bible (KJV, 1611)).  In the Greek, the word was used also to mean "a deceitful woman" although etymologists note that may have been to suggest she was “a binder, an entangler”, the sense from seira (cord, rope).  In zoology, the mammalian sense appeared first in French in Les entretiens d'Ariste et d'Eugène (Conversations between Ariste & Eugène) by the French Jesuit priest Dominique Bouhours (1628–1702) while the use to describe the aquatic salamander was introduced in 1766 by Swedish zoologist & physician Carl Linnaeus (1707–1778 and styled as Carl von Linné after 1761) for a genus of reptiles.  In organic chemistry, scientists noted the attraction exerted by the sirens of mythology and coined “sirenin” to describe a sexual attraction pheromone in some fungi of the genus Allomyces.  Less charmingly, in early twentieth century Australian urban slang, a “stem siren” was a prostitute; in the Australian way, often it was clipped to “stem”.

The use to describe the mechanical device “making a warning sound” was first recorded in 1879 when they were installed on steamboats and this may have been imitative of the similar French word.  In the course of the twentieth century, the things were adapted as audible warning devices for many purposes including air raids, emergency service vehicles and fire alarms (now mandatory in residential accommodation in many jurisdictions).  In schools, workplaces and other geographically large sites, they were used to mark the start and finish of shifts, lessons, meal breaks etc.  The Elizabethan era (1558-1603) adjectives sirenean, sirenian, sirenic, sirenical & sireny) went extinct but as late as the 1940s, the spelling variation sireen still occasionally appeared and not always as a deliberate archaism.  The writer & critic John Ruskin (1819–1900 and known for his fondness for young. beautiful creatures), used the rare sirenic so with that imprimatur, some modern aesthete might be tempted to revive the form.  Siren is a noun & verb, sirenize is a verb, sirenlike, sirenless, sirenical & sirenic are adjectives; the noun plural is sirens or (the rare) sirenes.

Odysseus and the Sirens

In Greek mythology, the Sirens were sea demons, half-woman and half bird (although there were variants in the tales).  They were said to be the daughters of Achelous and either Melpomene, Sterope or Terpsichore, Phorcys often named as their father, while it was also related they were born of the blood of Achelous when he was wounded by Heracles. There were two Sirens in the Odyssey (Homer’s eighth century BC epic poem following the ten year trek of King Odysseus (Ulysses) returning to his home island Ithaca after the decade-long Trojan War) but in the works of later authors there could be four (more often three).  Historians attribute variations in the myths to (1) authorial innovation or (2) in an age of limited literacy, poetry spread in oral performance, meaning details could become blurred.  What was consistent was the musical virtuosity of the Sirens, a popular depiction of them as a three-piece ensemble, one playing the flute and one the lyre while another sang her songs.

Sirens and the Night (1865), oil on canvas by William Edward Frost (1810-1877).

The Sirens used their lyrical and earthly charms to lure sailors to their death; attracted by the enchanting music and voices, the seduced seafarers would sail their ships too close to the rocky coast of the nymphs' island and there be shipwrecked.  Not untypically for the myths of Antiquity, the Sirens are said to have had many homes.  The Romans said they lived on some small islands called Sirenum scopuli while later authors place them variously on the islands of Anthemoessa, on Cape Pelorum, on the islands of the Sirenuse, near Paestum, or in Capreae.  All were places with rocky coasts and tall cliffs and thus for ships potentially lethal places although the fate of sailors was more gruesome, the Sirens devouring them.  The Argonauts sailed close to the Sirens, but, using the same principle as “radio jamming” in the twentieth century, Orpheus sang as long as the crew was within earshot of them (“drowning out their signal”), so none were lured (except the unfortunate Butes, carried away by Aphrodite after he fell victim).

Temptress in Siren mode: Lindsay Lohan, First Point (2011).

It was Odysseus who most famously escaped the sirens.  Longing to hear their songs but, forewarned by Circe and having no wish to be shipwrecked and devoured, he had his sailors fill their ears with beeswax, rendering them deaf.  Then, he ordered he be tied to the mast, telling his crew that whatever he said, they were not to release him but instead tighten the knots, not cutting the bonds until the ship had sailed far from the coast.  Of course, approaching the rocks, he heard the lovely voices and implored the crew to release him but they followed their skipper’s orders, not setting him free until the danger had passed.  Some writers claimed the Sirens were doomed to die if a man heard their singing and escaped and, as Odysseus sailed off, they flung themselves into the waters and drowned but, among the myths, that was not always their fate.  The idea of the Sirens persists in idiomatic use: the term “siren sound” refers to words or something exerting a particularly compelling attraction but “siren song” or “siren call” can be used of something not directly audible, such as the thoughts evoked by a painting or even a concept; populism, fascism & communism have all been described thus.  That idiomatic use describes an enticing but dangerous appeal, especially a misleading one.

The Roman Poet Ovid (Publius Ovidius Naso; 43 BC–17 AD) wrote that the Sirens were once ordinary girls, companions of Persephone; in his telling they were something “nice girls from good families who got led astray by mixing with the wrong crowd”.  When Persephone was abducted by Pluto, they asked the gods for wings so they could soar in the skies to help them search for their lost companion; that’s the most romantic explanation for the “half-woman and half bird” motif.  More unforgiving writers attributed the transformation to (1) the anger felt by Demeter when the Sirens failed to prevent the abduction of her daughter or (2) the wrath of Aphrodite who sought to deprived them of their feminine beauty because they scorned the pleasures of love.  A twist on that was that after their transformation, they made the mistake of trying to rival the muses who avenged the slight by plucking the Sirens’ feathers.  In a literary sense, the nymphs certainly exerted on authors a siren call.  The tomb of the Siren Parthenope was said to be in Naples, where her body had been cast upon the shore and that geographical connection is in the narrative strand in which Parthenope was a hauntingly beautiful Phrygian girl who fell in love with Metiochus but could not bring herself to break her vow of chastity.  She cut off her hair and ran off into exile in Campania (close to Naples) where she dedicated herself to Dionysus, something possibly the origin of Aphrodite’s disapprobation; it was Aphrodite who turned Parthenope into a Siren as punishment for abandoning her love.  The Sirens were also said to sing for the blessed in the Islands of the Blessed; because they could play the celestial harmonies, they were often depicted on sarcophagi.

First Point (2011) by Richard Phillips (b 1962), hosted by Vimeo by courtesy of Richard Phillips and Gagosian Gallery.  Lindsay Lohan as a siren; it would seem almost a calling.  Screened in conjunction with the 54^th international exhibition of the Venice Biennale (June 2011), First Point was a short film said by the diredctor to represent a “new kind of portraiture.”  Filmed in Malibu, California, the piece was included in the Commercial Break series, presented by Moscow's Garage Center for Contemporary Culture (now Garage Museum of Contemporary Art); although the promotional notes indicated it would include footage of the ankle monitor she helped make famous, the device doesn't appear in the final cut.

Directed by: Richard Phillips & Taylor Steele

Director of Photography: Todd Heater

Costume Designer: Ellen Mirojnick

Creative Director: Dominic Sidhu

Art Director: Kyra Griffin

Editor: Haines Hall

Color mastering: Pascal Dangin for Boxmotion

Music: Tamaryn & Rex John Shelverton

The Chrysler Air Raid Siren and the Firepower V8  

According to Guinness World Records, the loudest sirens ever were the 350-odd built in the early 1950s by Chrysler for the US government and installed around the country to warn of an impending nuclear attack by the Soviet Union.  The maximum volume the devices generated was recorded (at a distance of 100 feet (30.5 m)) as 138 dB (decibels), a level at which a human would suffer at least temporary deafness if within around 200 feet (60 m) during operation.  Guinness noted the compressor discharge throughput at peak volume was 74 m³ (2,610 cubic feet at 7 lb per square inch) of air per second and the physics of fluid dynamics (air a fluid in this context) was such this would have caused a sheet of paper in the path spontaneously to ignite.  By comparison the now retired SST (supersonic transport) airline Concorde at take-off produced noise levels between 112-114 dB at a distance of 100 feet and even afterburner equipped military jets (F-16, F-35 etc) haven’t been recorded as generating levels as high as 138 dB.

Although there were ebbs in the tensions, the “High Cold War” is defined usually as the time between the early 1950s and late 1960s, the public's fear of thermo-nuclear war at sometimes acute. In popular culture, the subject was a popular with authors and film-makers, the best known including the book On the Beach (1957) by Neville Shute (1899-1960) and the memorable film Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964), based on the novel Red Alert (1958) by Peter George (1924–1966).  The US government made many preparations for such an event, notably building vast underground facilities where essential personnel (members of the administration, the Congress, their families and servants) could live until it was safe for them to emerge into the post-apocalypse world and stake claim to whatever habitable real-estate remained.  The taxpayers who paid for these facilities were of course rather less protected but the government in 1952 did install warning sirens in cities; people might still be vaporized by comrade Stalin's (1878-1953; Soviet leader 1924-1953) H-Bombs but they would know what was coming so there was that.

US war-room film set for Stanley Kubrick's (1928-1999) film version of Dr Strangelove.  Upon becoming president in 1981, Ronald Reagan (1911-2004, POTUS 1981-1989) was reported as being disappointed nothing quite so dramatic actually existed, the White House's “Situation Room” something like what would be used by an insurance company to conduct sales training seminars.  The story is thought likely apocryphal but there is documentary evidence Mr Reagan did sometimes confuse historic fact with what he's seen in movies.

The early version of the warning siren was co-developed by Chrysler and Bell Labs and named CBVS (Chrysler Bell Victory Siren) which, given the consequences of nuclear war, seems at least optimistic.  Technically, although the acoustic properties met the specification, the drawback was the devices manually were activated and controlled, requiring someone physically to be on-location to start the thing and, being directional, rotate it so the sound would be broadcast 360^o.  The obvious flaw in that was, were  there to be a nuclear attack in the area, the job-description, at least potentially, was self-sacrificial, something comrade Stalin doubtless would have thought just the part of the cost of war with the unfortunate patriotic soul posthumously to be awarded the coveted Герой Советского Союза (Hero of the Soviet Union) decoration.  However, neither the White House or the Pentagon liked the optics and revised specifications for the sirens were issued.

Photograph by Rob Storms of Chrysler Air Raid Siren atop Rochester Fire Department Maintenance Building, Rochester, Monroe County, New York.

Chrysler's engineers responded with a more elaborate device, automated and remotely administrated; because it was developed wholly in-house, the corporate-themed acronym CARS (Chrysler Air Raid Siren) was coined.  Introduced in 1952, the new design was powered by Chrysler’s new, 331 cubic inch (5.4 litre) Hemi-head V8, rated at what was then a stellar 180 HP (134 kW), a three-stage compressor added to increase output.  Instead of demanding a doomed operator, there was a control panel connected (with nothing more than the two-pair copper cables that became familiar as Cat3 “phone-wire”) to dedicated phone lines so it could be activated either by local civil defense authorities or the military.  The big V8 provided sufficient power to both increase the dB and the geographical coverage, the siren able to be heard over an area of some 15.8 square miles (41 km²), an impressive number given the electric sirens used today for tornado and tsunami warnings have an effective footprint of only some 3.9 square miles (10 km²).

Chrysler Air Raid Siren being delivered on the back of a Dodge flatbed truck, 1953.

In 1952, there was no engine better suited to the task than Chrysler’s new “FirePower” Hemi V8.  Applying their wartime experience building a number of high-output, multi-cylinder engines (the most remarkable a V16 aero-engine rendered obsolete by jet technology before it could be used), the FirePower featured hemispherical combustion chambers and was the corporation’s first use of OHV (overhead valves) in passenger vehicle engines.  Both OHV and hemispherical combustion chambers had been around for decades but, before long, Chrysler would make a (trade-marked) fetish of “Hemi”, continuing cheerfully to use the name for a range of V8s introduced in 2003 even though they no longer used a true hemi-head, the design unable to be adapted to meet modern exhaust emission laws.  The so-called “third generation” Hemi remains available still although how long it will last will be a matter of the interplay of politics and demand.  Doubtless, it’s on Greta Thunberg’s (b 2003) long (and expanding) hit-list and that she and the engine arrived on planet Earth in the same year won't much impress her.

Chrysler FirePower 392 cubic inch (6.4 litre) V8 in 1957 Chrysler 300C Convertible.  In the jargon, the pair of four barrel carburetors were dubbed  “dual quads”.

First sold in 1950, the FirePower appeared first as a 331, growing over the decade to 354 (5.8) and then 392 (6.4) before being retired in 1959, the wedge-headed alternative with increased displacement a cheaper path to power (the hemi heads needing special machining and the valve-train was heavy and labor-intensive to assemble).  Chrysler and Imperial shared the engines but remarkably, in an approach that would today shock accountants and efficiency experts, the companion divisions (De Soto & Dodge) produced nine different hemi-head V8s with capacities between 241 (4.0) and 345 (5.6) with relatively little commonality of components between them all.  The last of the FirePowers were noted also for being one of the first engines offered with electronic fuel injection (built with analogue components) but while that offered real advantages over the mechanical systems then available in a handful of models in Europe and the US, the technology was then too fragile to be reliable and most of the 16 sold (reputedly all but one) were recalled and retro-fitted with a pair of faithful four barrel carburetors.  In 1964, the hemi-head was revived for a racing engine and, to satisfy the regulatory body that had been unimpressed with the use of such a thing in a series for “stock” cars, it was made available to the public between 1966-1971, this time called “Street Hemi”.  In 426 cubic inch (7.0 litre) form, it gained a reputation Chrysler would exploit for decades after production ended.

Some 350 CARS were built, all by the Chrysler's M&I (Marine & Industrial Engine Division, based in Trenton, Michigan) with some maintained in service as late as the 1970s.  During the era of détente, the last were retired, some sold to museums or collectors while other were just abandoned because, mounted atop tall buildings to maximize their acoustic coverage, the cost of removal far exceeded their value as units to be re-purposed or scraped.  At least three fully functional CARS still exist, one in a remote part of Texas where it’s safe to stage the occasional demonstration of the sound.  During these displays, the clear zone (minimum safe distance) extends outwards 320 feet (97.5 metres) but even at this range, anyone standing directly in front of the projection horns would find the experience uncomfortable, prolonged exposure risking some damage to the eardrums.  Although directional, there’s much “sound soak” in the device's proximity so just operating the siren from the side control panel requires hearing protection (acoustic earmuffs rated at a minimum 30 dB).

CARS at the Don Garlits Museum of Drag Racing, re-awakened after decades, 1997.

One collector attracted to them was Don Garlits (b 1932) who, in the post-war years, was among the most innovative and successful drivers and builders in the then wildly popular sport of drag-racing and it was with highly-modified Chrysler Hemis (the HP (horsepower) of which would come to be generated in thousands) he built his reputation.  In 1997, a documentary crew from the UK visited Garlits and saw one of the old CARS sitting neglected in the storeroom where it’d sat for decades after having spent some 20 years in salt-laden air atop a Florida high-rise.  Remarkably, after doing little more than connecting a battery and checking the oil and coolant, once a carburetor had been bolted on with a can of gas (petrol) rigged up, it started almost immediately, a reasonable achievement given it had never before run on gasoline because the CARS always used propane.  As Garlits over the decades had discovered a ¼ mile (402 metres) at a time, the FirePower Hemi was a tough old thing.

The Siren Suit

Weldon pattern for siren suit, 1940.  Home-made clothes used to be common and wartime conditions made the practice spike.  The production and distribution of patterns was a significant industry, enduring, at a smaller scale, to this day.

Unrelated to the seductive Sirens of mythology, the “siren suit” was a World War II (1939-1945) era coining describing a garment “ideal to wear when there was a risk of an air-raid siren sounding”.  The design wasn’t new; they would have been familiar to previous generations as the “overalls” mechanics and such wore to protect their clothing from oil and dirt, the novelty being the application.  Because “the Blitz” (the bombing campaign against London and other English cities waged by the Luftwaffe (the German Air Force) in 1940-1941) was conducted at night, that meant air-raid sirens were most likely to sound when people were in bed and the attraction of the “overall-like” siren suit was it could be worn over nightwear (pyjamas, nighties and such), meaning that upon being wakened by the siren, time would not be wasted getting dressed before rushing off to seek shelter; all one need to put on was one’s shoes.  With wool, silk & cotton supplies being diverted to military production, recycled blends using the more available rayon came increasingly to be used and the versatility of the synthetic made it popular; available in a variety of weights, unlike fabrics made from natural fibres, it was not subject to creasing or shrinkage.  In 1940, the most commonly requested feature was a “hood” and these came to be included on many, often with a lining for additional warmth.  Stylistically and conceptually, the siren suit can thus be imagined as a “proto-onesie”, one of the twenty-first century’s more controversial garments, not so much for what is it (warm, comfortable, convenient) but for where some choose to frequent while wearing one (Walmart, fast food outlets and such).

Wartime individualism, circa 1941: Despite wartime privations, fashion sense didn’t die and ways were found to individualize even the most starkly functional items.

As this publicity shot indicates, gas-masks were in the UK of 1940 a piece of compulsory kit for civilians, the use of poison gas expected by many in politics and the military.  Ironically, of all the leaders in the era, it was only Winston Churchill (1875-1965; UK prime-minister 1940-1945 & 1951-1955) who was enthusiastic about the use of gas as a weapon, thinking it ideal to deploy on beaches in the event of an amphibious assault by the Wehrmacht (the German military (1935-1945)).  Even Adolf Hitler (1889-1945; Führer (leader) and German head of government 1933-1945 & head of state 1934-1945) explicitly ruled out the use of poison gas, despite the Germans also holding large stocks.  Although in 1918 Hitler had learned of Germany’s capitulation when in hospital recovering from the temporary blindness suffered after being gassed, his unwillingness to use gas was not a humanitarian gesture but because the unpredictability of the wind (in Europe the “westerly” (ie from west to east) the prevailing type) made use too risky.

As a unisexual style, by 1940, the siren suit wouldn’t have been too shocking a challenge to the fashion police.  Although the tradition is longer still, in the West, women routinely (if not universally) had been wearing “trousers” since the mid-nineteenth century (for sport, work & leisure, the light and convenient “pyjama-suit” welcomed by many) and, during World War I (1914-1918), as in increasing numbers they entered the industrial workforce to replace men conscripted for military service, the sheer functionality of trousers was compelling (and often, for safety reasons, compulsory); women in overalls became commonplace.  Given the purpose, the early siren suits (the less pleasing “blitz suit” never catching on) were designed with little in mind except comfort, warmth and speed in donning so most were fastened with a zip though the photographic record confirms buttons or snap-fittings were also used, mass-production made immediately possible because they could be sewed on the same lines used to make overalls.  Winston Churchill often was photographed in his siren suit and while that promoted use, it also confirmed the style was not “slimming”.  Even more than overalls, siren suits seem to have featured generously-sized pockets, a thoughtful addition permitting those disturbed from their slumber quickly to stash valuables and the essentials needed for a few hours in an air-raid shelter while retaining the recommended “hands-free” status.  Coincidentally, the siren suit fitted in with the wartime “fashion zeitgeist” the rationing of fabrics and other materials imposing on clothing simplicity and a reduction in bulk.  Even after that economic imperative had faded, that simplicity would remain influential in the post-war years, most obviously in the minimalist movement, effects achieved with severe cuts rather than fussy embellishments.

Winston Churchill (left) in siren suit with comrade Stalin (right), the Kremlin, Moscow, August 1942.

The prime minister had earlier worn the same Siren suit on a visit to the White House to meet Franklin Delano Roosevelt (FDR, 1882–1945, POTUS 1933-1945) and it was much admired, the FLOTUS (Eleanor Roosevelt (1884–1962; FLOTUS 1933-1945) even saying she’d like to have one made for her husband, if “…the wool shortage” would allow it.  Decades later, during his visit to Washington DC, Volodymyr Zelenskyy (b 1978, President of Ukraine since 2019) found his similar sartorial choice not as well-received.  According to Churchill, even before the war he’d been inspired by the “coveralls” worn by coal miners to commission the London tailors Turnbull & Asser to create a bespoke one for him, finding it just the thing to wear when enjoying his hobby of painting.  Upon the country being threatened by bombing, he ordered several, his specifications recorded in the company’s archives: “Generously cut, with two breast pockets, a zip fastening, roomy side pockets, a belt and pleats to the front of the trousers.”  To suit their client’s whims, Turnbull & Asser made them in various fabrics including the same pinstripe as some of his suits, a durable serge twill and one in a velvet of striking emerald green, still on display in their London store.  There’s nothing to suggest he ever worn one made from utilitarian rayon.

Otrovert

Otrovert (pronounced ott-roh-vert)

A person unable to feel a connection to social groups or collectives; despite being welcomed and included in social settings, they feel like outsiders.

2025: A coining by US psychiatrist Dr Rami Kaminski (b 1954), who first used the word in his book his book The Gift of Not Belonging (2025), the construct being the Spanish otro (other; another) + -vert.  Otro was from the Latin alter, altera & alterum (the other), ultimately from the primitive Indo-European hélteros (the other of two); it may be compared with the Portuguese outro (from the Old Galician-Portuguese outro, from the Latin alterum (the other)) and the French autre (from Old French autre (another), from the Latin alterum).  The –vert suffix was from the Latin vertere (to turn) and was used to refer to a person with a particular personality which manifests when in the presence of others.

Otrovert is a noun; the noun plural is otroverts.  Because otrovert is a “hot word” (newly coined or an adaptation of an existing word and one which has in a short time become popular), most lexicographers are tagging it as “provisional”, the majority of “hot words and phrases” (think “six-seven”) fading from use and never gaining critical mass.  Even the idea of “popular: had (in this context) shifted because whereas once it could take months or years for a word or phrase to spread into general use, on the various platform on the internet, proliferation can be close to instant.  However, the tools used to assess “use” are rather brute-force and often are counting appearances in “lists” rather than “general use”.  For those reasons, in the technical sense, derived forms really don’t (yet) exist but if constructed the list (based on the model of other “-verts”) might include the nouns otrovertist, otroverting & otrovertness, the verb & adjective otroverted, adjectives otrovertish & otrovertesque & otrovertive and the adverbs otrovertedly & otrovertly.

Google ngram (a quantitative and not qualitative measure): Because of the way Google harvests data for their ngrams, they’re not literally a tracking of the use of a word in society but can be usefully indicative of certain trends, (although one is never quite sure which trend(s)), especially over decades.  As a record of actual aggregate use, ngrams are not wholly reliable because: (1) the sub-set of texts Google uses is slanted towards the scientific & academic and (2) the technical limitations imposed by the use of OCR (optical character recognition) when handling older texts of sometime dubious legibility (a process AI should improve).  Where numbers bounce around, this may reflect either: (1) peaks and troughs in use for some reason or (2) some quirk in the data harvested.

An ambivert is a person neither clearly extroverted nor introverted, but has characteristics of each, the construct being ambi- +‎ -vert.  Ambi- was from the Latin ambo (both) and was a doublet of the New Latin amphi-, from the Ancient Greek ἀμφί (amphí) (on both sides).  The dexter element in the Medieval Latin meant “right” and ambidexter thus was understood as “both hands being like a right hand”.  In English, the ambi- prefix is most familiar in “ambidextrous” (possessing an equal or functionally comparable ability to handle objects with both hands (in writing, music, sport etc) although it has from time to time been used figuratively (not taking sides in conflicts or being equally adept in more than one medium, genre, style etc) and even as a humorous synonym for “bisexual”.  When used in psychology, historically, ambiversion described someone with characteristics of both extroversion and introversion and thus suggested a “balanced personality”, the subject choosing to manifest the different characteristics according to what the circumstances seemed to demand.  Ambivert thus does not imply some sort of split personality or the existence of a condition like bi-polar disorder (the old manic depression) but simply reflects an individual able to undertake their social interactions in an appropriate manner.

Because the “vert words” are not really part of academic or clinical physiology, the definitions can be “elastic” and while centovert (being in the middle between introvert and extrovert) may be a synonym of ambivert, it may also be nuanced in that it suggests someone unable (or at least unwilling) to engage in introverted or extroverted behaviour, regardless of the circumstances.  A variant of the ambivert is the omnivert (someone fits into both extremes of the extroversion-introversion personality spectrum), the construct being omni + -vert.  Omni- ultimately was from the Latin omnis (all).  Again, because the “verts” are pop-psychology words there’s little to be gained from attempting to “parse the overlaps” (ie where one ends and another begins) and seems likely omniversion is simply an “enabling pre-condition” for one to possess if one is to attain the desirable “balanced state” of ambiversion.  Nobody seems yet to have coined ultravert, hypervert or ubervert but one need not spend long on social media to see the why such labels might be handy.

A self-described introvert: Lindsay Lohan explains she's an introvert; 2019 interview by broadcaster Howard Stern (b 1954).

Like other “-verts” of this ilk, otrovert was built on the model of the familiar introvert & extravert, the construct being intro + -vert.  An introvert (pronounced in-truh-vurt) is an individual who prefers (sometimes actively seeks) tranquil environments, limits social engagement and tends to a greater than average preference for solitude.  In anatomy & zoology there’s a technical meaning “a part (typically a hollow, cylindrical structure) that is or can be introverted, or turned in on itself (ie invaginate)) but the most commonly used is the psychological sense: a person characterized by concern primarily with their own thoughts and feelings.  Introverts are noted often for having a disposition that finds social engagement at least tiresome (and sometimes threatening), thus the preference for quiet solitude.  Introvert seem first to have appeared in print in the 1660s and was from the New Latin intrōvertere, the construct being intrō (within) + vertere (to turn).  The prefix intro- was from the Latin intro- (inwards) & intrā (within) + -ō (used as a verbalizer).  Although it’s not infrequent for introvert to be used as a synonym for “shy” (and in terms of observed behaviour the two phenomena can appear indistinguishable), they are definitionallly distinct.  While shyness is associated with timidity and social anxiety, introverts have a lack of interest in interpersonal engagement and a limited endurance for social contact; what that means is while the behaviours can often be the same, the underlying motivations differ.

Slaughterhouse-Five (1969) by Kurt Vonnegut.

Introvert & extrovert are popular terms of self-description but they can also be aspirational and while the classic stereotype is of the introvert who “wishes they were more outgoing” there are other types.  The US pediatrician Dr Mark Vonnegut (b 1947) wrote short stories and in one he described his father’s (the author Kurt Vonnegut (1922-2007)) desire to be a cynical, grumpy old man who despaired of humanity but could never quite manage it because of his “inherent optimism”.  As Dr Vonnegut put it, he was “…like an extrovert who wanted to be an introvert, a very social guy who wanted to be a loner, a lucky person who would have preferred to be unlucky. An optimist posing as a pessimist, hoping people will take heed.”  Explaining the difference, he added: “Introverts almost never cause me trouble and are usually much better at what they do than extroverts.  Extroverts are too busy slapping one another on the back, team building, and making fun of introverts to get much done.  Extroverts are amazed and baffled by how much some introverts get done and assume that they, the extroverts, are somehow responsible.”  On the basis of his clinical experience, he observed: “I understand perfectly why some of my autistic patients scream and flap their arms--it's to frighten off extroverts.”

An extrovert (pronounced ek-struh-vurt) is described typically as an outgoing, gregarious person who thrives in dynamic environments and seeks to maximize social engagement; in the jargon of psychology, it refers to someone characterized by extroversion; a person concerned primarily with the physical and social environment, thus the usual presentation as a person with a disposition energized through social engagement who tends to languish or chafe in solitude.  The word extrovert (the alternative spelling extravert (an example of the influence of German on psychology) is now rare) also emerged in the 1660s, the construct being extro- + vert.  In this case, extro- was a pseudo-Latinism prefix based upon the Latin extra- (outside, beyond), under the influence of the distinction between the Latin intro- (inwards) & intra- (inside; within).  In English, formations using the prefix tend to be restricted to words formed as antonyms of terms formed with intro-.

Introvert & extrovert (in their literal senses) were since the late seventeenth century used in science and medicine but both in the twentieth century entered general use when certain works by the Swiss psychiatrist, Carl Jung (1875–1961) were translated from German into English.  What seems to have given the words their greatest impetus was the appearance of commentaries on Jung written for a general audience and for these purposes binary concepts like “introvert” and “extrovert” were useful devices to encapsulate layers of meaning although the trigger may have been the 1918 paper Psycho-Analytic Study of August Comte [1798-1857; a seminal figure in sociology] by psychologist Dr Phyllis Blanchard (1895-1986).  Being a woman, Dr Blanchard has been neglected by history but, like the Austrian psychiatrist Sigmund Freud (1856-1939), Jung became what would now be called a “celebrity” psychoanalyst and that happened because advances in their field (and neurology) had made the public fascinated with the human mind and its processes (especially dreams).  Reflecting what may possibly be a professional distaste at their jargon ending up in pop-psychology texts, technical papers often use the spelling “extravert”, following Jung and his contemporaries.

The Gift of Not Belonging (2025) by Dr Rami Kaminski (b 1954).  Psychiatrist Dr Kaminski is the founder and director of the Institute for Integrative Psychiatry in New York City.

Dr Kaminski describes The Gift of Not Belonging as “…the first book to explore the distinct personality style of the otrovert - someone who lacks the communal impulse and does not fit in with any social group, regardless of its members - and to reveal all the advantages of being an otrovert and how otroverts contribute to the world.”  He explained that while otroverts enjoy deep and fulfilling one-on-one relationships, within groups they feel alienated, uncomfortable, and alone.  Unlike introverts, who crave solitude and are easily drained by social interactions, otroverts can be quite gregarious and rarely tire from one-on-one socialising; unlike loners, or people who have been marginalised based on their identity, otroverts are socially embraced and often popular - yet are unable to conform with what the group collectively thinks or cares about.  Dr Kaminski positions all this as “the great gifts of being an otrovert” by which he means someone with no affinity for a particular group is not constrained by their sense of self-worth being conditioned on the group's approval.  A champion of the otrovert, Dr Kaminski suggests they “must not be harassed to take part, but allowed to revel in their glorious difference.”

Despite vying with “psychopath” for the title of “most popular” words from psychology, neither introvert and extrovert have ever been used as diagnostic terms in the American Psychiatric Association's (APA) Diagnostic and Statistical Manual of Mental Disorders (DSM); that doesn’t mean they’re not used by clinicians, just that they’re not part of the formal jargon.  That might seem curious given their not infrequent appearances in the published history of personality psychology including Jung’s original typology (codified in their most refined form in the 1920s), the ubiquitous MBTI (Myers–Briggs Type Indicator) and the Big Five model, where Extraversion is one of the five major personality traits.  These frameworks are however psychological, not psychiatric.  The DSM does of course have an extensive section on personality disorders and many of the traits related to introversion & extraversion appear including in (1) Avoidant Personality Disorder (social inhibition—links superficially to introversion but is not the same thing) and Histrionic or Narcissistic Personality Disorders (social boldness—superficially “extraverted” traits).

However, what the DSM’s editors have in recent decades done is to avoid the use of potentially ambiguous labels and focus instead on behavioural criteria that may indicate impairment or pathology.  Especially since the 1970s, the DSM has acknowledged (even championed) the idea that many “things” once classified as deviant are really part of the “normal” human condition; reflecting that paradigm, introversion & extraversion came to be understood as “normal-range” personality traits, not indicators of disorder.  As a general principle, the DSM appears to restrict the use of terms to instances where they relate to clinically significant impairment (the emphasis on the effect on the patient rather than the mechanics of process).  This approach was institutionalized with the release of DSM-5 (2013) in which the model clearly had become one of trait-based personality assessment.

To make the point, there exists in DSM-5 & DSM-5-TR (2022) the “Alternative DSM-5 Model for Personality Disorders, Section III” which describes personality traits that (more or less) correspond to what popular culture calls extraversion and introversion.  The editors however avoid the two popular words and instead breaks personality into trait domains with pathological versions of ordinary traits.  What general readers think of a “introversion” now appears in the DSM as “Detachment” although this is not pathologized unless it manifests in maladaptive extremes (chronic or persistent withdrawal; avoidance of social interaction; intimacy avoidance; a reluctance to form close relationships; anhedonia (inability to experience pleasure); mistrust of others; restricted affectivity (limited emotional expression)).  So, introverts can to some degree be “happy” with their state and just prefer frequent solitude and what the DSM calls “detachment” is invoked only when the trait is causing significant impairment or distress.

In the popular imagination, “extraversion” is associated with sociability, talkativeness, outgoing behaviour, enthusiasm (ie someone who is the “life of the party”).  That’s also obviously a “spectrum condition” and the DSM has never listed a single domain which could be classed as “high extraversion” which is good because high sociability isn’t intrinsically pathological.  Rather, should extraversion becomes maladaptive or extreme, the DSM classifies it across several domains:

(1) Attention-seeking (a facet of Antagonism) which manifests especially in Histrionic Personality Disorder.  Symptoms include an excessive need for approval, dramatic or provocative behaviour and an Intense desire to be the centre of attention.

(2) Grandiosity (a facet of Antagonism) which is characteristic of Narcissistic Personality Disorder, the symptoms including social boldness (masking fragile self-esteem) and entitlement and arrogance (which, in many cases, doesn’t manifest)

(3) Impulsivity & Risk Taking (a facet of disinhibition).  This is outgoing, sensation-seeking behaviour in its pathological form and is associated with thrill-seeking, poor impulse control and a tendency to act without considering the consequences

(4) Low Detachment: This is acknowledged as the “adaptive end of Detachment” but the editors seem to list it only to “close the circle”; it’s there because logically it has to be but is certainly not treated as a disorder.

So the DSM intentionally avoids the introvert/extrovert dichotomy which is how starkly it’s understood in popular use.  This “either-or” approach obviously doesn’t map onto the way the DSM treats personality traits as spectrums with only the margins (ie the dysfunctional extremes) described.  What that does is acknowledge there is introversion & extraversion which part of the “normal” human condition and not pathological.  Additionally it’s acknowledged the behavior which in one subject may indicate “significant impairment or distress” might in another not be of concern.

Demand

Demand (pronounced dih-mand (U) or dee–mahnd (non-U))

(1) To ask for with proper authority; claim as a right.

(2) To ask for peremptorily or urgently.

(3) To call for or require as just, proper, or necessary.

(4) In law, to lay formal claim to.

(5) In law, to summon, as to court.

(6) An urgent or pressing requirement.

(7) In economics, the desire to purchase, coupled (hopefully) with the power to do so.

(8) In economics, the quantity of goods that buyers will take at a particular price.

(9) A requisition; a legal claim.

(10) A question or inquiry (archaic).

1250-1300: From Middle English demaunden and Anglo-French demaunder, derived from the Medieval Latin dēmandāre (to demand, later to entrust) equivalent to dē + mandāre (to commission, order).  The Old French was demander and, like the English, meant “to request” whereas "to ask for as a right" emerged in the early fifteenth century from Anglo-French legal use.  As used in economic theory and political economy (correlating to supply), first attested from 1776 in the writings of Adam Smith.  The word demand as used by economists is a neutral term which references only the conjunction of (1) a consumer's desire to purchase goods or services and (2) hopefully the power to do so.  However, in general use, to say that someone is "demanding" something does carry a connotation of anger, aggression or impatience.  For this reason, during the 1970s, the language of those advocating the rights of women to secure safe, lawful abortion services changed from "abortion on demand" (ie the word used as an economist might) to "pro choice".  Technical fields (notably economics) coin derived forms as they're required (counterdemand, overdemand, predemand etc).  Demand is a noun & verb, demanding is a verb & adjective, demandable is an adjective, demanded is a verb and demander is a noun; the noun plural is demands.

Video on Demand (VoD)

Directed by Tiago Mesquita with a screenplay by Mark Morgan, Among the Shadows is a thriller which straddles the genres, elements of horror and the supernatural spliced in as required.  Although in production since 2015, with the shooting in London and Rome not completed until the next year, it wasn’t until 2018 when, at the European Film Market, held in conjunction with the Internationale Filmfestspiele Berli (Berlin International Film Festival), that Tombstone Distribution listed it, the distribution rights acquired by VMI, Momentum and Entertainment One, and VMI Worldwide.  In 2019, it was released progressively on DVD and video on demand (VoD), firstly in European markets, the UK release delayed until mid-2020.  In some markets, for reasons unknown, it was released with the title The Shadow Within.

Video on Demand (VoD) and streaming services are similar concepts in video content distribution but there are differences.  VoD is a system which permits users to view content at any time, these days mostly through a device connected to the internet across IP (Internet Protocol), the selection made from a catalog or library of available titles and despite some occasionally ambiguous messaging in the advertising, the content is held on centralized servers and users can choose directly to stream or download.  The VoD services is now often a sub-set of what a platform offers which includes content which may be rented, purchased or accessed through a subscription.

Streaming is a method of delivering media content in a continuous flow over IP and is very much the product of the fast connections of the twenty-first century.  Packets are transmitted in real-time which enables users to start watching or listening without waiting for an entire file (or file set) to download, the attraction actually being it obviates the need for local storage.  There’s obviously definitional and functional overlap and while VoD can involve streaming, not all streaming services are technically VoD and streaming can also be used for live events, real-time broadcasts, or continuous playback of media without specific on-demand access. By contrast, the core purpose of VoD is to provide access at any time and streaming is a delivery mechanism, VoD a broad concept and streaming a specific method of real-time delivery as suited to live events as stored content.

The Mercedes-Benz SSKL and the Demand Supercharger

Modern rendition of Mercedes-Benz SSLK in schematic (left) and re-rendered with with "blueprint effect" (right), illustrating the drilled-out chassis rails (here depicted without the reinforcing metal sheets added to ensure structural integrity)  The title is misleading because the four SSKLs built all were commissioned in 1931 (although it's possible one or more used a modified SSK chassis constructed in 1929).  All SSK chassis were built between 1928-1932 although the model remained in the factory's catalogue until 1933. 

The Mercedes-Benz SSKL was one of the last of the road cars which could win a top-line Grand Prix.  An evolution of the earlier S, SS and SSK, the SSKL (Super Sports Kurz (short) Leicht (light)) was notable for the extensive drilling of its chassis frame to the point where it was compared to Swiss cheese; reducing weight with no loss of strength (although the longitudinal spars adjacent to the engine and the front bearing points of the rear leaf springs were reinforced with metal sheets concealing some of the drilled holes).  The SSKs and SSKLs were famous also for the banshee howl from the engine when the supercharger was running; nothing like it would be heard until the wail of the BRM V16s twenty years later.  It was called a demand supercharger because, unlike some constantly-engaged forms of forced-induction, it ran only on-demand, in the upper gears, high in the rev-range, when the throttle was pushed wide-open.  Although it could safely be used for barely a minute at a time, when running, engine power jumped from 240-odd horsepower (HP) to over 300.  The number of SSKLs built has been debated and the factory's records are incomplete because (1) like many competition departments, it produced and modified machines "as required" and wasn't much concerned about documenting the changes and (2) many archives were lost as a result of bomb damage during World War II (1939-1945); most historians suggest there were four or SSKLs, all completed (or modified from earlier builds) in 1931.  The SSK had enjoyed great success in competition but even in its heyday was in some ways antiquated and although powerful, was very heavy, thus the expedient of the chassis-drilling intended to make it competitive for another season.  Lighter than the SSK by 125 kg (275 lb), at 1352 kg (2980 lb), the SSLK was by race-car standards still a heavyweight but the reduction in mass did to a degree ameliorate the issues of brake & tyre wear but the higher speeds attained also made the anyway marginal braking capabilities more of a challenge for the drivers.  The SSKL enjoyed a long Indian summer and even on tighter circuits where the bulk meant it could be out-manoeuvred, sometimes it still prevailed by virtue of durability and sheer power.

Rudolf Caracciola (1901–1959) and SSKL in the wet, German Grand Prix, Nürburgring, 19 July, 1931.  Alfred Neubauer (1891–1980; racing manager of the Mercedes-Benz competition department 1926-1955) maintained Caracciola "...never really learned to drive but just felt it, the talent coming to him instinctively."

Sheer power there certainly was because in parallel with the chassis engineers trimming weight, the engine-development team massaged more power from the SSK’s supercharged, 7.1 litre (431 cubic inch) straight-six.  The approach was wholly conventional including increasing the throughput of the 18-vane Roots supercharger so to ensure advantage was taken of the increased flow-rate, the size of the intake and exhaust valves were enlarged by 7%.  All of this of course increased internal stresses so the crankshaft was modified, complimented by larger counterweights on the crank pins.  The tough old engine responded well.  In racing trim, the SSK had generated 180 (HP) horsepower which rose to 250 with the supercharger engaged but in the SSKL the revisions saw power rise to 240 or a remarkable 300 with the blower running.  Fuel consumption was of course high and the increased power increased tyre wear but none of the competition could match the power-to-weight ratio of 4½ per HP.

The Amalgam Collection's 1:8 scale model of the Mercedes-Benz SSKL that won the 1931 Mille Miglia: US$26,995.

Sometimes too it got lucky.  When the field assembled in 1931 for the Fünfter Großer Preis von Deutschland (fifth German Grand Prix) at the Nürburgring, even the factory acknowledged that at a race-weight of 1350 kg-odd, the SSKLs, whatever their advantage in horsepower, stood little chance against the nimble Italian and French machines which weighed-in at some 200 KG (440 lb) less.  However, on the day there was heavy rain with most of race conducted on a soaked track and the twitchy Alfa Romeos, Maseratis and the especially skittery Bugattis proved less suited to the slippery surface than the truck-like but stable SSKL, the lead built up in the rain enough to secure victory even though the margin narrowed as the surface dried and a visible racing-line emerged.  Time and the competition had definitely caught up by 1932 however and it was no longer possible further to lighten the chassis or increase power so aerodynamics specialist Baron Reinhard von Koenig-Fachsenfeld (1899-1992) was called upon to design a streamlined body, the lines influenced both by his World War I (1914-1918 and then usually called "the World War") aeronautical experience and the "streamlined" racing cars which had been seen in the previous decade.  At the time, the country greatly was affected by economic depression which spread around the world after the 1929 Wall Street crash, compelling Mercedes-Benz to suspend the operations of its competitions department so the one-off "streamliner" was a private effort (though with some tacit factory assistance) financed by the driver (who borrowed some of the money from his mechanic!).

The streamlined SSKL crosses the finish line, Avus, 1932.

The driver was Manfred von Brauchitsch (1905-2003), nephew of Major General (later Generalfeldmarschall (Field Marshal)) Walther von Brauchitsch (1881–1948; Oberbefehlshaber (Commander-in-Chief) of OKH (Oberkommando des Heeres (the German army's high command) 1938-1941).  An imposing but ineffectual head of the army, Uncle Walther also borrowed money although rather more than loaned by his nephew's mechanic, the field marshal's funds coming from the state exchequer, "advanced" to him by Adolf Hitler (1889-1945; Führer (leader) and German head of government 1933-1945 & head of state 1934-1945).  Quickly, Hitler learned the easy way of keeping his mostly aristocratic generals compliant was to loan them money, give them promotions, adorn them with medals and grant them estates in the lands he'd stolen during his many invasions.  His "loans" proved good investments.  Beyond his exploits on the circuits, Manfred von Brauchitsch's other footnote in the history of the Third Reich (1933-1945) is the letter sent on April Fools' Day 1936 to Uncle Walther (apparently as a courtesy between gentlemen) by Baldur von Schirach (1907-1974; head of the Hitlerjugend (Hitler Youth) 1931-1940 & Gauleiter (district party leader) and Reichsstatthalter (Governor) of Vienna 1940-1945) claiming he given a "horse whipping" to the general's nephew because a remark the racing driver was alleged to have made about Frau von Schirach (the daughter of Hitler's court photographer!).  It does seem von Schirach did just that though it wasn't quite the honorable combat he'd claimed: in the usual Nazi manner he'd arrived at von Brauchitsch's apartment in the company of several thugs and, thus assisted, swung his leather whip.

Stromlinienrennwagen (streamlined racing car): A replica of the 1932 Mercedes-Benz SSKL built by the factory in 2018-2019.

Von Brauchitsch the younger denied ever making the remarks and von Schirach was lucky not to have been hanged by the IMT (International Military Tribunal) which tried some of the surviving Nazis in the first Nuremberg Trial (1945-1946).  Had evidence of his conduct in Vienna been brought before the court, he'd have received the death sentence he deserved.  Unlike the German treasury, the mechanic got his money back and that loan proved a good investment, coaxing from the SSKL a victory in its final fling.  Crafted in aluminum by Vetter in Cannstatt, the body was mounted on von Brauchitsch's race-car and proved its worth at the at the Avusrennen (Avus race) in May 1932; with drag reduced by a quarter, the top speed increased by some 12 mph (20 km/h) and the SSKL won its last major trophy on the unique circuit which rewarded straight-line speed like no other.  It was the last of the breed; subsequent grand prix cars would be pure racing machines with none of the compromises demanded for road-use.

Evolution of the front-engined Mercedes-Benz grand prix car, 1928-1954

1928 Mercedes-Benz SS.

As road cars, the Mercedes-Benz W06  S (1927-1928) & SS (1928-1930) borrowed unchanged what had long been the the standard German approach in many fields (foreign policy, military strategy, diplomacy, philosophy etc): robust engineering and brute force; sometimes this combination worked well, sometimes not.  Eschewing refinements in chassis engineering or body construction as practiced by the Italians or French, what the S & SS did was achieved mostly with power and the reliability for which German machinery was already renowned.  Although in tighter conditions often out-manoeuvred, on the faster circuits both were competitive and the toughness of their construction meant, especially on the rough surfaces then found on many road courses, they would outlast the nimble but fragile opposition.

1929 Mercedes-Benz SSK.

By the late 1920s it was obvious an easier path to higher performance than increasing power was to reduce the SS's (Super Sport) size and weight.  The former easily was achieved by reducing the wheelbase, creating a two-seat sports car still suitable for road and track, tighter dimensions and less bulk also reducing fuel consumption and tyre wear, both of which had plagued the big, supercharged cars.  Some engine tuning and the use of lighter body components achieved the objectives and the SSK was in its era a trophy winner in sports car events and on the grand prix circuits.  Confusingly, the "K" element in the name stood for kurz (short) and not kompressor (supercharger) as was applied to some other models although all SSKs used a supercharged, 7.1 litre (433 cubic inch) straight-six. 

1931 Mercedes-Benz SSKL.

The French, British and Italian competition however also were improving their machinery and by late 1930, on the racetracks,  the SSK was becoming something of a relic although it remained most desirable as a road car, demand quelled only by a very high price in what suddenly was a challenging economic climate.  Without the funds to create anything new and with the big engine having reached the end of its development potential, physics made obvious to the engineers more speed could be attained only through a reduction in mass so not only were body components removed or lightened where possible but the chassis and sub-frames were drilled to the point where the whole apparatus was said to resemble "a Swiss cheese".  The process was time consuming but effective because, cutting the SSK's 1520 kg (3350 lb) heft to the SSKL's more svelte 1352, combined with the 300-odd HP which could be enjoyed for about a minute with the supercharger engaged, produced a Grand Prix winner which was competitive for a season longer than any had expected and one also took victory in the 1931 Mille Miglia.  Although it appeared in the press as early a 1932, the "SSKL" designation is retrospective, the factory's extant records listing the machines either as "SSK" or "SSK, model 1931".  No more than four were built and none survive (rumors of a frame "somewhere in Argentina" apparently an urban myth) although some SSK's were at various times "drilled out" to emulate the look and the appeal remains, a replica cobbled together from real and fabricated parts sold at auction in 2007 for over US$2 million; this was when a million dollars was still a lot of money.  

Stromlinienrennwagen (streamlined racing car): 1932 Mercedes-Benz SSKL.

The one-off bodywork (hand beaten from aviation-grade sheet aluminum) was fabricated for a race held at Berlin's unique Automobil-Verkehrs- und Übungsstraße (Avus; the "Automobile traffic and training road") which featured two straights each some 6 miles (10 km) in length, thus the interest in increasing top speed and while never given an official designation by the factory, the crowds dubbed it die Gurke (the cucumber).  The streamlined SSKL won the race and was the first Mercedes-Benz grand prix car to be called a Silberpfeil (silver arrow), the name coined by radio commentator Paul Laven (1902-1979) who was broadcasting trackside for Südwestdeutsche Rundfunkdienst AG (Southwest German Broadcasting Service); he was struck by the unusual appearance although the designer had been inspired by an aircraft fuselage rather than arrows or the vegetable of popular imagination.  The moniker was more flattering than the nickname Weiße Elefanten (white elephant) applied to S & SS which was a reference to their bulk and not a use of the phrase in its usual figurative sense.  The figurative sense came from the Kingdom of Siam (modern-day Thailand) where elephants were beasts of burden, put to work hauling logs in forests or carting other heavy roads but the rare white (albino) elephant was a sacred animal which could not be put to work.  However, the owner was compelled to feed and care for the unproductive creature and the upkeep of an elephant was not cheap; they have large appetites.  According to legend, if some courtier displeased the king, he could expect the present of a white elephant.  A “white elephant” is thus an unwanted possession that though a financial burden, one is “stuck with” and the term is applied the many expensive projects governments around the world seem unable to resist commissioning.

Avus circuit.  Unique in the world, it was the two long straights which determined die Gurke's emphasis on top speed.  Even the gearing was raised (ie a numerically lower differential ratio) because lower engine speeds were valued more than low-speed acceleration which was needed only once a lap.

The size of the S & SS was exaggerated by the unrelieved expanses of white paint (Germany's designated racing color) although despite what is sometimes claimed, Ettore Bugatti’s (1881–1947) famous quip “fastest trucks in the world” was his back-handed compliment not to the German cars but to W. O. Bentley’s (1888–1971) eponymous racers which he judged brutish compared to his svelte machines.  Die Gurke ended up silver only because such had been the rush to complete the build in time for the race, there was time to apply the white paint so it raced in a raw aluminum skin.  Remarkably, in full-race configuration, die Gurke was driven to Avus on public roads, a practice which in many places was tolerated as late as the 1960s.  Its job at Avus done, die Gurke was re-purposed for high-speed tyre testing (its attributes (robust, heavy and fast) ideal for the purpose) before "disappearing" during World War II.  Whether it was broken up for parts or metal re-cycling, spirted away somewhere or destroyed in a bombing raid, nobody knows although it's not impossible conventional bodywork at some point replaced the streamlined panels.  In 2019, Mercedes-Benz unveiled what it described as an "exact replica" of die Gurke, built on an original (1931) chassis.    

1934 Mercedes-Benz W25.

After building the replica Gurke, Mercedes-Benz for the first time subjected it to a wind-tunnel test, finding (broadly in line with expectations) its c_d (coefficient of drag) improved by about a third, recording 0.616 against a standard SSK's 0.914.  By comparison, the purpose-built W25 from 1934 delivered a 0.614 showing how effective Baron Koenig-Fachsenfeld's design had been although by today's standards, the numbers are not of shapes truly "slippery".  Although "pure" racing cars had for years existed, the W25 (Werknummer (works number) 25) was the one which set many elements is what would for a quarter-century in competition be the default template for most grand prix cars and its basic shape and configuration remains recognizable in the last front-engined car to win a Word Championship grand prix in 1960.  The W25 was made possible by generous funding from the new Nazi Party, "prestige projects" always of interest to the propaganda-minded party.  With budgets which dwarfed the competition, immediately the Mercedes-Benz and Auto Unions enjoyed success and the W25 won the newly inaugurated 1935 European Championship.  Ironically, the W25's most famous race was the 1935 German Grand Prix at the Nürburgring, won by the inspired Italian Tazio Nuvolari (1892–1953) in an out-dated and under-powered Alfa-Romeo P3, von Brauchitsch's powerful W25 shredding a rear tyre on the final lap.  However, the Auto Union's chassis design fundamentally was more farsighted; outstanding though the engine was, the W25's platform was, in many ways, eine bessere Gurke (a better cucumber) and because its limitations were inherent, the factory "sat out" most of the 1936 season to develop the W125.

1937 Mercedes-Benz W125.

Along with the dramatic, mid-engined,  V16 Auto Union Type C, the W125 was the most charismatic race car of the "golden age" of 1930s European circuit racing.  When tuned for use on the fastest circuits, the 5.7 litre (346 cubic inch) straight-eight generated over 640 HP and in grand prix racing that number would not be exceeded until the turbocharged engines (first seen in 1977) of the 1980s.  The W125 used a developed version of the W25's 3.4 (205) & 4.3 (262) straight-eights and the factory had assumed this soon would be out-performed by Auto Union's V16s but so successful did the big-bore eight prove the the Mercedes-Benz V16 project was aborted, meaning resources didn't need to be devoted to the body and chassis engineering which would have been required to accommodate the bigger, wider and heavier unit (something which is subsequent decades would doom a Maserati V12 and Porsche's Flat-16.  The W125 was the classic machine of the pre-war "big horsepower" era and if a car travelling at 100 mph (160 km/h) passed a W125 at standstill, the latter could accelerate and pass that car within a mile (1.6 km).

A W125 on the banked Nordschleife (northern ribbon (curve)) at Avus, 1937.  At Avus, the streamlined bodywork was fitted because a track which is 20 km (12 miles) in length but has only four curves puts an untypical premium on top-speed.  The banked turn was demolished in 1967 because increased traffic volumes meant an intersection was needed under the Funkturm (radio tower), tower and today only fragments of the original circuit remain although the lovely art deco race control tower still exists and was for a time used as restaurant.  Atop now sits a Mercedes-Benz three-pointed star rather than the swastika which flew in 1937. 

1938 Mercedes-Benz W154.

On the fastest circuits the streamlined versions of the W125s were geared to attain 330 km/h (205 mph) and 306 km/h (190 mph) often was attained in racing trim.  With streamlined bodywork, there was also the Rekordwagen built for straight-line speed record attempts and one set a mark of 432.7 km/h (268.9 mph), a public-road world speed record that stood until 2017.  Noting the speeds and aware the cars were already too fast for circuits which had been designed for, at most, velocities sometimes 100 km/h (50 mph) less, the governing body changed the rules, limiting the displacement for supercharged machines to 3.0 litres (183 cubic inch), imagining that would slow the pace.  Fast though the rule-makers were, the engineers were quicker still and it wasn't long before the V12 W154 was posting lap-times on a par with the W125 although they did knock a few km/h off the top speeds.  The rule change proved as ineffective in limiting speed as the earlier 750 KG formula which had spawned the W25 & W125.

1939 Mercedes-Benz W165.

An exquisite one-off, the factory built three W165s for the single purpose of contesting the 1939 Tripoli Grand Prix.  Remarkable as it may now sound, there used to be grand prix events in Libya, then a part of Italy's colonial empire.  Anguished at having for years watched the once dominant Alfa Romeos enjoy only the odd (though famous) victory as the German steamroller flattened all competition (something of a harbinger of the Wehrmacht's military successes in 1939-1940), the Italian authorities waited until the last moment before publishing the event's rules, stipulating the use of a voiturette (small car) with a maximum displacement of 1.5 litres  (92 cubic inch).  The rules were designed to suit the Alfa Romeo 158 (Alfetta) and Rome was confident the Germans would have no time to assemble such a machine.  However, knowing Adolf Hitler (1889-1945; Führer (leader) and German head of government 1933-1945 & head of state 1934-1945), still resenting what happened at the Nürburgring in 1935, would not be best pleased were his Axis partner (and vassal) Benito Mussolini (1883-1945; Duce (leader) & Prime-Minister of Italy 1922-1943) to enjoy even this small victory, the factory scrambled and conjured up the V8-powered (a first for Mercedes-Benz) W165, the trio delivering a "trademark 1-2-3" finish in Tripoli.  As a consolation, with Mercedes-Benz busy building inverted V12s for the Luftwaffe's Messerschmitts, Heinkels and such, an Alfa Romeo won the 1940 Tripoli Grand Prix which would prove the city's last.      

 

1954 Mercedes Benz W196R Strómlinienwagen (literally "streamlined car" but translated usually as "Streamliner".

A curious mix of old (drum brakes, straight-eight engine and swing axles) and new (a desmodromic valve train, fuel injection and aerodynamics developed in a wind-tunnel with the help of engineers then banned from being involved in aviation), the intricacies beneath the skin variously bemused or delighted those who later would come to be called nerds but it was the sensuous curves which attracted most publicity.  Strange though it appeared, it was within the rules and clearly helped deliver stunning speed although the pace did expose some early frailty in road-holding (engineers have since concluded the thing was a generation ahead of tyre technology).  It was one of the prettiest grand prix cars of the post war years and the shape (sometimes called "type Monza", a reference to the Italian circuit with long straights so suited to it) would later much appeal to pop-artist Andy Warhol (1928–1987) who used it in a number of prints.

1954 Mercedes-Benz W196R.  In an indication of how progress accelerated after 1960, compare this W196R with (1) the W25 of 20 years earlier and (2) any grand prix car from 1974, 20 years later. 

However, although pleasing to the eye, the W196R Strómlinienwagen was challenging even for expert drivers and it really was a machine which deserved a de Dion rear suspension rather than the swing axles (on road cars the factory was still building a handful with these as late as 1981 and their fudge of semi-trailing rear arms (the "swing axle when you're not having a swing axle") lasted even longer).  Of more immediate concern to the drivers than any sudden transition to oversteer was that the aluminium skin meant they couldn't see the front wheels so, from their location in the cockpit, it was difficult to judge the position of the extremities, vital in a sport where margins can be fractions of a inch.  After the cars in 1954 returned to Stuttgart having clouted empty oil drums (those and bails of hay was how circuity safety was then done) during an unsuccessful outing to the British Grand Prix at Silverstone, a conventional body quickly was crafted and although visually unremarkable, the drivers found it easier to manage and henceforth, the Strómlinienwagen appeared only at Monza.  There was in 1954-1955 no constructor's championship but had there been the W196R would in both years have won and it delivered two successive world driver's championships for Juan Manuel Fangio (1911–1995).  Because of rule changes, the three victories by the W196R Strómlinienwagen remain the only ones in the Formula One World Championship (since 1950) by a car with enveloping bodywork.