Note 38 — PART II. (continued 2)

Since the preceding pages have been printed, I have seen a self-extinguishing gas-lamp, invented by Mr. Clegg. This lamp is so constructed, that the gas cannot flow to the burner, when the flame becomes extinguished. If, therefore, the lamp should be blown out, and the stop-cock which supplies the gas be left open, the extinction of the flame will effectually shut the valve. The action of this lamp depends upon the expansibility of a metallic rod, heated by the flame of the lamp, and thus keeping open the valve, whereas, when the lamp is extinguished, and the rod becomes cold, it contracts to its natural dimensions, and, by that means, effectually closes the valve. The same engineer has invented a machine, which both measures and registers, in the absence of the observer, the quantity of gas delivered by any pipe communicating with a gas-light main. The machine occupies a space of about two feet by one foot, and, if put up in a room, house, or other place, where gas is burnt, will, at any time, by mere inspection, give an account of the quantity of gas consumed in that place during any given time. On the present occasion, it would not become me to say more on these subjects, which, no doubt, Mr. Clegg will make known to the public; I shall only remark, that these contrivances do signal honour to the talents and abilities of the inventor; and that they will render the greatest services to those who are engaged in the gas-light illumination.