wder was used in all firearms until smokeless and other type
propellants were invented in the latter 1800's. "Black" powder (which
was sometimes brown) is a mixture of about 75 parts saltpeter
(potassium nitrate), 15 parts charcoal, and 10 parts sulphur by
weight. It will explode because the mixture contains the necessary
amount of oxygen for its own combustion. When it burns, it liberates
smoky gases (mainly nitrogen and carbon dioxide) that occupy some 300
times as much space as the powder itself.

Early European powder "recipes" called for equal parts of the three
ingredients, but gradually the amount of saltpeter was increased until
Tartaglia reported the proportions to be 4-1-1. By the late 1700's
"common war powder" was made 6-1-1, and not until the next century was
the formula refined to the 75-15-10 composition in majority use when
the newer propellants arrived on the scene.

As the name suggests, this explosive was originally in the form of
powder or dust. The primitive formula burned slowly and gave low
pressures--fortunate characteristics in view of the barrel-stave
construction of the early cannon. About 1450, however, powder makers
began to "corn" the powder. That is, they formed it into larger
grains, with a resulting increase in the velocity of the shot. It was
"corned" in fine grains for small arms and coarse for cannon.

Making corned powder was fairly simple. The three ingredients were
pulverized and mixed, then compressed into cakes which were cut into
"corns" or grains. Rolling the grains in a barrel polished off the
corners; removing the dust essentially completed the manufacture. It
has always been difficult, however, to make powder twice alike and
keep it in condition, two factors which helped greatly to make gunnery
an "art" in the old days. Powder residue in the gun was especially
troublesome, and a disk-like tool (fig. 44) was designed to scrape the
bore. Artillerymen at Castillo de San Marcos complained that the
"heavy" powder from Mexico was especially bad, for after a gun was
fired a few times, the bore was so fouled that cannonballs would no
longer fit. The gunners called loudly for better grade powder from
Spain itself.

How much powder to use in a gun has been a moot question through the
centuries. According to the Spaniard Collado in 1592, the proper
yardstick was the amount of metal in the gun. A legitimate culverin,
for instance, was "rich" enough in metal to take as much powder as