Gas and Petroleum Engines

by H. de Graffigny

Two years after the Abbé de Hautefeuille had made public his idea, in a memoir entitled A Method of Raising Water by means of Gunpowder, the Dutch savant Huyghens published a similar work, describing an apparatus consisting of a cylinder with two leather exhaust pipes, forming valves; to the bottom of the cylinder was screwed a small box in which gunpowder was to be ignited. The effect of the explosion was to drive out a large quantity of heated gas through the valves, which closed again when it had passed. The gas remaining in the cylinder soon cooled down, so that the pressure within it fell below that of the surrounding atmosphere, and caused the piston to be forced down by the excess of atmospheric pressure.

This operation was certainly very crude, and, as might have been expected, scarcely came up to the expectations of its inventor. The idea was, however, not allowed to rest here, and Papin set himself to find out some better agent to replace the gunpowder, whose action was uncertain and, to say the least of it, brutal. The result of his experiments pointed clearly to the condensation of steam as being the most suitable method of producing a space filled with a gas at a lower pressure than that of the atmosphere, and many inventors, following in his footsteps, adopted this process for working pumping engines. In consequence of the great success of the steam engine, which was due to the genius of Watt and his successors, the idea of using combustion to act directly as a motive power was lost sight of for a great number of years, and it was not till the year 1791 that any suggestion was made which was an improvement on the engines of De Hautefeuille and Huyghens. The inventor, this time an Englishman, by name John Barber, specified in his patent, in somewhat laconic language, the use of a mixture of a hydrocarbon gas and air, and its explosion in a vessel which he termed an exploder. Several years later, in 1794, Robert Street, also an Englishman, took out a patent for the production of an explosive vapour by means of a liquid and air, ignited by a flame in a suitable cylinder so as to drive machinery and pumping engines. Petroleum or any other inflammable liquid was allowed to drip on to the heated bottom of a cylinder so as to be vaporized and drive up the piston.

Philip Lebon, of Brachay, the creator of the coal gas industry in France, took out a patent in 1799, setting forth very clearly the principle and construction of an engine using the explosion of coal gas as its motive power. Lebon, in fact, devised his gas-producing plant with the intention of only using the coal gas in his gas engine, lighting by its means being quite an afterthought. In a second patent two years afterwards he describes a more perfect apparatus, in which a pump is provided for compressing the mixture of coal gas air, and also an electric machine worked by the engine itself for igniting the compressed mixture. Unfortunately, the career of this fertile inventor came to an abrupt end by his assassination in 1804. It is highly probable, that if he had lived gas engines would have come into general use at the beginning of the century instead of nearly sixty years later.

From 1799 up till the year 1860, in which the first really practical gas engine made its appearance, several schemes were put forward, some of them not lacking in ingenuity, of which the most interesting were due to Welman, Wright, Johnston, and Barnett. Wright’s machine was particularly well thought out and constructed. The double-acting cylinder was placed in a vertical position and the gases were ignited by a gas-jet. A centrifugal governor regulated the pumps which compressed the explosive mixture in the cylinder, and at the same time varied the composition of the explosive mixture so as to always be proportional to the work which was required to be done. When we come to consider that this engine was brought out in the year 1833, it is wonderful that it did not meet with greater success, but this was probably due to the fact that the steam engine was at that period coming greatly into favour, and for the time being completely eclipsed all other forms of motive power.

About this time a double-acting gas engine was devised by Johnston, using pure hydrogen and oxygen as the explosive mixture, in the proportion of two volumes of hydrogen to one of oxygen. After the explosion and driving forward of the piston, the combined gases being cooled were precipitated as water, and a partial vacuum obtained which was used during the return stroke. This idea was a highly ingenious one, but failed owing to the high price of hydrogen and oxygen, but perhaps some day, when these obstacles have been removed, this idea may once more be taken up.

In 1838 William Barnett took out a patent for an engine based on the same principle as that of Lebon. Two pumps compressed separately the combustible gas and the air and forced the mixture under pressure into the cylinder. The explosion was caused by a small gas-jet, communication between it and the cylinder being set up at the right moment by a revolving valve. The gas-jet was situated in the valve itself, and was so arranged that during half a revolution it was turned towards the outside, and was then lighted by a second jet, and during the remainder of the revolution it communicated with the interior of the cylinder and ignited the explosive mixture. This was the first gas motor in which the ignition was from the outside, and in which the explosive gases were at the same time under pressure. In most modern gases the same result is obtained, but the original and rather crude method of obtaining it has of course been much modified and improved. During the next few years several patents were taken out relating to the same subject. In 1844 John Reynolds suggested using a battery which should white-heat a platinum wire in order to ignite the gases, the ignition taking place at the required moment by means of an automatic switch closing the battery circuit.

In 1850 Stéphard recommended a magneto-electric machine driven by the engine itself instead of the primary battery.

Barsanti and Matteucci described in 1857 an atmospheric motor, their arrangement of the parts being afterwards adopted by Otto and Langen. A Bunsen cell supplied current to a De la Rive multiplier, causing a stream of sparks to pass between two fine points situated within the combustible mixture. In 1858 and 1859 Degrand explained in two patents a gas engine in which the gases were compressed in the cylinder itself. Owing to mechanical difficulties his machine was impracticable, but the idea forms an important step in the history of gas engines.

In 1860, when the Lenoir motor appeared, no other existed which was capable of regular and comparatively efficient work.

This machine, devised by Lenoir and constructed by Marinoni, had the appearance of a double-acting horizontal steam engine. The explosive mixture was ignited by an electric spark produced by a Ruhmkorff coil and a primary battery. The machine ran smoothly and regularly and its cost was moderate: among the advantages which it possessed at that time over other forms of motive power, were the absence of a cumbrous boiler and costly foundations, and the little care and attention necessary to keep it in working order. So great was its success at the time, that many people prophesied that the steam engine would soon become extinct.