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power of expansion and explosion, and that asthe air sent into the candle of a safety lamp isfrequently explosive, it is necessary for securityto prevent it from breaking the lamp, or com-municating with the surrounding air. Thesepreventives Dr. Clanny discovered, and sometime afterwards Sir H. Davy examined his ap-paratus.

After this it certainly was not difficult todiscover that the air might be sent throughoil instead of water, and that a piston mightbe used instead of bellows. This howeverwas so evidently but a simple alteration of Dr.Clanny’s invention, that it never was broughtpublicly forward ; or if brought forward wasrejected —that it was tried I have sufficientevidence to testify.

Dr. Clanny had experimented with a tube,having a small perforation to convey the airfrom a pair of double blast bellows. Afterthis it was not difficult to find out that smallair apertures would answer the same purpose:from hence the safety concentric canals, &c.follow in regular succession of ideas ; and ul-timately the gauze wire apertures are the ex-tremity of refinement, upon a principle clearlyoriginating with Dr. Clanny. And until I amtold that any person invented a safety lampbefore Dr. Clanny, or that subsequent inyen-