By the old method of soldering, there is great danger of setting fire to houses and public buildings: the destruction of the corn market of Paris, and of the Cathedrals of Chartres and of Bruges, by fire, was partly owing to the negligence of plumbers; a negligence for which there could be no reason, if the new method of soldering had been introduced, since it is only necessary to turn a cock in order to extinguish or rekindle, at any moment, the jet of gas which serves for the plumber’s tool. By means of the new apparatus, a soldering flame can be conducted to a distance of several fathoms without the dangerous necessity of lighting a brasier to heat irons, to melt masses of solder, and to carry the whole into the midst of complicated carpentry work. The disuse of solder will also greatly reduce the price of plumber’s work, without, however, diminishing the demand for the services of the workmen. The disuse of seams or overlapping, which from this new mode of connecting lengths of lead will almost entirely be given up, will alone occasion a considerable saving in the quantity of lead employed. The ease with which lead of from one-thirtieth to one-tenth of an inch in thickness may be soldered, and defects repaired, will permit of the substitution of this, in many cases, for thicker lead, and thus diminish the expense; perhaps, also, it will give rise to the use of lead for purposes to which it has not yet been applied, or the return to others, in which from motives of economy it has been superseded by other metals. The plumber will also be indebted to M. de Richemont’s method for several important improvements. He will be able in future to make internal joints wherever a jet of flame can be introduced and directed; to reconstruct on the spot, of pure lead, any portion of a pipe, a vase, or a statue, that may have been removed or destroyed; to execute in rapid succession any number of solderings; to repair in a few minutes all dents, cracks, and flaws, in sheets or pipes of new lead; to remove entirely the enormous edges or knots left by the old-fashioned joints, and that without weakening them; to give, in short, to works of lead a precision of execution, and a solidity, unattainable up to this time. Autogenous soldering will also be of great assistance to several chemical manufactures, where it is so important to have large vessels of lead without alloy. By uniting a number of sheets into one, vessels of pure lead of any size may be formed for the process of acidification and concentration of saline solutions; for the formation of scouring vats employed by so many artisans who work metals; for vessels of every kind used to contain liquids which act upon tin solder.