to melt the copper.

TO PREVENT THE COPPER COOLING IN THE FURNACE.

When the copper cools in the furnace, be ready, as soon as you
perceive it, to cut it with a long stick while it is still in a
paste; or if it is quite cold cut it as lead is cut with broad and
large chisels.

IF YOU HAVE TO MAKE A LARGE CAST.

If you have to make a cast of a hundred thousand pounds do it with
two furnaces and with 2000 pounds in each, or as much as 3000 pounds
at most.

738.

HOW TO PROCEED TO BREAK A LARGE MASS OF BRONZE.

If you want to break up a large mass of bronze, first suspend it,
and then make round it a wall on the four sides, like a trough of
bricks, and make a great fire therein. When it is quite red hot give
it a blow with a heavy weight raised above it, and with great force.

739.

TO COMBINE LEAD WITH OTHER METAL.

If you wish for economy in combining lead with the metal in order to
lessen the amount of tin which is necessary in the metal, first