Note 11 — Chapter VI · INTERNAL COMBUSTION ENGINES

FOOTNOTE:

11. The fact that air is heated to combustion point by compression has long been known to the Chinese. In The River of Golden Sand, Captain Gill writes: "The natives have an apparatus by which they strike a light by compressed air. The apparatus consists of a wooden cylinder 2 1 / 2 inches long by 3 / 4 inch in diameter. This is closed at one end; the bore being about the size of a stout quill pen, an air-tight piston fits into this with a large flat knob at the top. The other end of the piston is slightly hollowed out, and a very small piece of tinder is placed on the top thus formed. The cylinder is held in one hand, the piston inserted and pushed about half-way down; a very sharp blow is then delivered with the palm of the hand on to the top of the knob; the hand must at the same time close on the knob, and instantly withdraw the piston, when the tinder will be found alight. The compression of the air produces heat enough to light the tinder; but this will go out again unless the piston is withdrawn very sharply. I tried a great many times, but covered myself with confusion in fruitless efforts to get a light, for the natives never miss it."