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October 1935: Harry Ricardo on the petrol engine - .PDF file.
Sir Harry Ricardo – who founded Ricardo in 1927 – was an important figure in the development of internal combustion engines, and in 1935 he shared his memories of the early years of motoring in The Engineer.

Ricardo first drove a car in 1898, he said — he’d have been 13 at the time. The engine — a horizontal single-cylinder job — had ‘all its working parts exposed to the winds of heaven and the dusts of the earth below — exposed to everything, in fact, apart from lubrication.’ The carburettor was particularly troublesome, he recalled: it was a wick carburettor, a technology which didn’t survive into the 20th century, being a large container a quarter-full of petrol in which several lengths of lamp-wick were suspended. Air was drawn past these wicks — where it would pick up petrol vapour — and into the engine, taking what was supposed to be a combustible mixture into the cylinders. ‘Seldom, if ever, did the engine and I agree as to the definition of a combustible mixture,’ Ricardo said. ‘It was an unfair debate, for the engine always had the last word, spat scornfully and then sulked.’ Eventually, he developed a technique for steering with one hand and feeding the engine with the other.
Although the wick carburettor was superceded, it bequeathed to the automotive industry a very unhelpful fuel standard, prizing volatility as the main determinant of fuel quality. This led to later engines developing ‘knock’ — a ringing sound which caused extreme aggravation. Ricardo, as a Cambridge undergraduate in 1904, helped out with research into knocking, which was determined to result from the fuel-air mixture detonating in the cylinder.
This problem was eventually solved by adding tetraethyl lead to the petrol (the invention of Wallace Carruthers, the unluckiest chemist in history, who also devised the use of chlorofluorocarbons as aerosol propellants) and Ricardo turned his attention to diesel, where as he put it ‘the relation of the fuel to the engine is far less intimate.’ Diesel allowed engine designers to supercharge as much as they liked, but designers had to work out a way of delaying ignition long enough for the fuel-air mixture to penetrate into the cylinder, ‘otherwise we would get beautifully smooth running with perfect control, but very little power.’ This was done by altering the properties of the fuel, but by 1935, there was still very little prospect of a standard diesel. ‘Different types of high-speed diesel engines have widely different tastes,’ Ricardo said.
The full article can be read here.
There is some fantastic writing and turns of phrase in Ricardo’s article. eg. “It would seem.. that the performance of the petrol engine is mainly one of the dietary and that is to the chef rather than to the engineer to whom we must turn our attention….while the chef’s menu may be invigorating it is also apt to be indigestible or even poisonous.”
Fantastic!
“eventually solved by adding tetraethyl lead to the petrol (the invention of Wallace Carruthers, the unluckiest chemist in history,”
Not sure it can be termed “Bad Luck” when something you invent/ apply to a problem becomes as ubiquitous as leaded petrol or CFC’s. I will agree with anyone that those two items were ultimately bad for the environment but I am not sure how he (or anyone else) could have known either how much lead and Flouro-carbon would be added to the environment in the subsequent 50 years after his invention and prior to it being noticed that it was a problem in the 1970-1980’s. or are we saying it was bad luck that his self lifting machine caused him to be strangled to death. I am sure he viewed himself as a great innovator as did most of his peers, Including Thomas Midgley.
Or are we actually talking about Thomas Midgley, who did all those things and not Wallace Caruthers who invented Nylon?
.” ..the invention of Wallace Carruthers, the unluckiest chemist in history, who also devised the use of chlorofluorocarbons as aerosol propellants…”
And polyamides, which became nylon! Interesting that Carruthers by-passed the poly-esters thinking that they were of less interest than the ‘amides’ -they have certainly proved him wrong!
Polyester filaments (and staple) were developed by Winfield (actually at the laboratory of Calico Printers in Accrington) My first ICI Fibres boss, one Raymond Speakman worked with Winfield: he was the mechanical Engineer who took the lab-scale concepts and created machinery to process such in quantity!
Carruthers had a very sad personal life: eventually committing suicide in the Hotel du Pont in Wilmington, Delaware: but surely his legacy lives on. Actually during WWII most nylon was reserved for military uses: glider tow ropes, parachute canopies and rigging lines, harnesses.
In the archives of the Irvin Parachute Co they have several nylon shutes that were used twice. Once by Allied air-crew baling-out over Germany. The second by German pilots who appreciated that their nylon construction was better/stronger, with less tendency to tear, than their ‘viscose’ based fabric’ The German pilots had them re-packed, and had their lives saved when they baled out over the UK!
Well worth a read is Ricardo Story: The Autobiography of Sir Harry Ricardo, Pioneer of Engine Research (SAE historical series)