How gunpowder is made.
The first knowledge of gunpowder, among European
nations, was in the 14th century, a German monk named Swartz
being regarded as the inventor; but that gunpowder was known thousands of years ago by the Hindoos and Arabs, is certain.
Ancient writers speak of a people living near the Ganges
that attacked their enemies ‘"with thunderbolts shot from their walls;"’ and ‘"with storms of lightnings and thunderbolts hurried from above."’ These were as far back as Alexander
, 300 B. C. Hindoo annals as far back as the time of Moses
speak of it.
Gunpowder is composed of saltpetre, sulphur and charcoal; and its operation is founded on the rapid combination and consequent expansion of gasses, set free by combustion of its parts.
The proportion of the ingredients used differs according to the use to which the powder is put. The United States Government formula 75 parts saltpetre, 12 5 sulphur, and 12 5 charcoal.
We give some of the various receipts in a table.
|U. S.||75||12 5||12 5|
Charcoal for gunpowder should be made of willow or alder trees.
Dogwood is also very good.
It should be charred at a temperature of 500 deg. The English cylinder gunpowder derives its name from charcoal made in cylindrical iron retorts, heated to a red heat.
The manufacture of gunpowder is an operation requiring skill.
The saltpetre and sulphur are first refined, the former by solving in water and the latter by fusing.
Each of the ingredients are then ground to powder and bolted.
They are then carefully weighed and mixed in a trough made for the purpose.
The compound is then put into the mill, 50 lbs. at a time, which is made of two revolving cast-iron rollers of three tons weight, revolving on a cast-iron plate, and ground three hours. It is kept moistened all the time with water, to prevent its forming dust.
It is then taken out of the mill, and in drying, forms cakes called mill cakes.
These are then broken up between grooved wooden rollers, and introduced into a hydraulic press, of 120 tons to the square foot.
The mixture comes out of this pressure in flat sheets half an inch thick.
It is then broken up and sifted.
It is then glazed by being placed in a barrel, 200 lbs. at a time, and revolved forty times a minute.
By this operation the edges of the grains and the loose particles on them are taken off by friction.
The quality of powder may be judged of by its firmness and uniformity, and by its not being easily crushed by the fingers, nor readily soiling them.
A sample flashed on white paper should blacken it but little, and not inflame it.
Powder being wet, and dried again, deteriorates in strength, though it still may be used.
A very powerful gunpowder is made by mixing two parts of chlorate of potassa with one of white sugar, and one ferrocylade of potassium.
This, when granulated, is white.
It will not absorb moisture, and may be readily made.
Care should be taken that no charcoal or sulphur be introduced.
It is not fit for iron guns, because it oxydizes them rapidly; but for brass guns, or bomb-shell, it serves an equally good, if not better purpose, than ordinary gunpowder.