204 PROOFS OF THE PROPERTIES OF H1DROGEN GAS.

plode with a loud report, and the inside of the bottle will becomemoist.

Remark.. ..It is prudent to wrap a handkerchief round the bot-tle, to prevent it from doing any injury if it should burst. Thesafest way of making this experiment is with a bottle of elasticgum.

The same experiment may be repeated with oxigen gas insteadof atmospheric air, changing the proportions and mixing onlyone part of oxigen gas with two of hidrogen. The explosionwill then be much louder than in the foregoing experiment.

Experiment IX.

To charge and Jire a cannon or pistol, ly means of hidrogengas.

This experiment may be made advantageously by means of anapparatus, sold under the name of the inflammable air pistol orcannon.

To charge this pistol nothing more is necessary, but to intro-duce its open end into a wide-mouthed bottle, filled with a mix-ture of oxigen and hidrogen gas; leaving it in for a few seconds,it is then to be stopped with a cork, and may be fired by the elec-tric spark, taken either from the prime conductor of the machineor a charged Leyden vial.

Experiment X.

The production of water ly detonating hidrogen and oxigengases

Is founded on the same principle. Take a strong glass tubeabout half an inch in diameter and twelve inches long, closed atone end and graduated into cubic inches or any other equi-distantparts. About half an inch from the closed end or top, twosmall holes are drilled opposite to each other, and into each ofthese a wire or conductor is to be cemented, so that the two