If the appreciation of the ballistic effects of the pyroxyle is yet in doubt, it is not the case as to its power and advantages under some other circumstances, principally in the blasting of rocks. The first experiments were made by Messrs. Combes and Flandin, mining engineers.

These experiments were made in a quarry of coarse calcary. A horizontal hole one foot deep was driven into the rock. The hole was driven in such a way that the rock was free on two faces, the upper and lower. The hole was 2 feet 4 inches below the upper face. They introduced into it 1 1/2 ounce of gun cotton which, after being packed, left an empty space 2 feet long. It was lighted; the explosion took place with very little noise, and without any projection. An appreciable time elapsed between the time that the match inflamed the cotton, and that when the mass was raised a little by dividing itself into pieces of 1/5 to 1/4 of a cubic yard. The mass thus blasted and divided above the hole extended 2 yards, at least, from the lower face, 3 yards at the left, and 1 1/2 yard from the right of the axis of the hole.

The total cube was about 7 cubic yards, the bed of the lower rock was fissured, as far as 2 1/2 feet from the axis of the hole. To produce the same effect with mining powder would have required half a pound.

These essays do not give the exact measure of the effects of the pyroxyle, and it requires further experiments. However, they permit us to hope that the substance will be used for mining purposes in the same manner as ordinary powder, and without requiring difficult precautions. Its property of burning without 11 smoke and smell will, we think, assure it the preference in all subterranean works.

We shall not speak, here, of the application of the pyroxyline in the preparation of fulminating powders, as in the sequel of this work we shall have a special article on that subject According to Messrs. Seguier and Clerget, there is no doubt that nitric paper will take an important place in pyrotechny. Paper pre-pared according to Mr. Pelouze's process, and dipped in solutions of nitrate of strontia, sulphate of copper, nitrate of baryta, have produced fine red, green, and white flames.

There is no doubt that trials will be made to apply to industry the expansive force of the pyroxyle, and Messrs. Lessere and Valod have made several experiments in applying to the movement of machines, the expansion pro-duccd by the deflagration of nitric paper; but those savants have been stopped in their essays by the explosion of the machinery. Experiments and time can only resolve these difficulties.

To the probable astonishment of the reader, we shall speak of the application of the pyroxy-line in the alimentary use. Mr. Pelouze at a meeting of the Academy of Sciences, speaks thus: "When we see nitric acid engages in organic combinations, in which it loses its ordinary properties, its odor, causticity, solubility, we ask if it is absolutely impossible one day to obtain alimentary substances by following a process, more or less directed in the sense I have indicated, that is, of introducing nitrogen into matters which do not contain it. For me, I am inclined to believe in the possibility of such a discovery."

Some years since, Messrs. Bernard and Bares experimented on the xyloidine as an alimentary substance. The results have been negative. Xyloidine has shown itself inalter-able in the intestines; it has remained white, deflagrant, insoluble in water, soluble in acetic acid and alcohol.