---+------+---------+--------+---------------------- No.|Nitre.|Charcoal.|Sulphur.| ---- ---+------+---------+--------+---------------------- 1 |76·00 | 14·00 | 10·00 |Powder of Bâe. 2 |76·00 | 12·00 | 12·00 | „ Grenelle. 3 |76·00 | 15·00 | 9·00 | „ M. Morveau. 4 |77·32 | 13·44 | 9·24 | „ Ditto. 5 |77·50 | 15·00 | 7·50 | „ M. Keffault. ---+------+---------+--------+---------------------- The first and third, after 200 discharges with the proof mortar, were declared the strongest, and the third proportions were adopted at the recommendation of the commissioners. Some few years elapsed, and the first, owing to its better keeping quality, was substituted, as it contained less charcoal, and a little more sulphur. The French Government having always been extremely impressed with the value of durability in gunpowder, they have since returned to their ancient proportions: 75 nitre, 12-1/2 charcoal, 12-1/2 sulphur. The charcoal, the absorbent of moisture, being further reduced, and the sulphur, the preserving ingredient, being increased in the same ratio. “Mr. Napier tried a small quantity made of nitre and charcoal only, and was much surprised to find it project a shot as far as the best powder made in the usual manner. It is found that, in small charges, sulphur is advantageous; but, in charges of several ounces, the projecting force is as great without as with it. Therefore, under certain circumstances, sulphur may be dispensed with; but to make a good gunpowder, nitre and charcoal are indispensable.” Amongst the brilliant discoveries of modern chemistry may be classed the development of the fact, that a chemical combination, to constitute the same compound, always takes place in definite and unalterable ratios. To select one example out of a multitude: one atom of carbon combining with two atoms of oxygen produces the gas; because more would answer no useful end. So, with reference to the sulphur, if it enter into combination only with the potassium--the base of the nitre--the sulphur should be in that proportion to form the sulphuret of that metal; and in this case there would be no superfluity, for that would only add to the weight of the charge of powder, and diminish its absolute and effective energy. The view of the case which we have taken supposes only two combinations, viz. carbon with oxygen, and sulphur with potassium. Should there be a more diversified play of affinities, and the several elements of the powder enter into more complicated action, accurate analysis would conduct us through all difficulties, and point out what the proportions of the ingredients ought to be in order to sustain that action, and to produce a perfect ultimate result.