The so-called carburator, or actual lamp-forge, is composed of a shell or chamber of cast-iron, with a false bottom or double compartment, into which air is to be forced by the aid of a smith's or circular bellows. On this shell stands an annular vessel of cast-iron, containing petroleum, supplied from a reservoir of equal level, by the help of a pipe. The heat of the lamp-forge keeps the petroleum in ebullition, and its vapour pours into the iron carburator, mixes with the compressed air, and rushes burning through a large copper funnel, capped by a thick tube in refractory fire-clay, and which contains the hottest portion of the flame; which is then suffered to play on the crucible or cupel containing the object to be heated, and which is surrounded by a cover or screen, to prevent the cooling effects of the atmosphere.
The blow-pipe attached to the apparatus is a flexible one, the interior being fitted with a copper spiral reaching to within one-third of an inch of the nozzle, and which renders the flame shorter and more compact than is the case with blow-pipes of the usual construction. The flame can be rendered oxidising or deoxidising at pleasure. For solders of every kind this blow-pipe is believed to be well adapted. The miniature lamp-forge is capable of melting, in ten minutes, fourteen ounces of copper, nickel, or cast-iron, or about twelve ounces of wrought-iron. The heat, therefore, is only equalled by that of the larger-sized table-furnaces fed with coke and urged by a continuous blast of air. But the action of these last-mentioned furnaces is brief, and when their supply of fuel is consumed, time is wasted in cooling and recharging them. The great merit of M. Quichenot's invention is, that the lamp-forge can be kept, without difficulty, at work for a considerable time, care being taken to guard against any heating of the petroleum in the reservoir of supply.
We have not been able to ascertain if these forges are to be seen in England; but we believe that information may be had, and the apparatus seen, by applying to M. le Directeur, Fabrique des Forges de Vulcain, 5 Rue Saint-Denis, Place du Châtelet, Paris.
Printed and Published by W. & R. CHAMBERS, 47 Paternoster Row, LONDON, and 339 High Street, EDINBURGH.