Of Mixing The Composition The Performance Of The Principal Part Of
fire-works depends much on the compositions being well mixed;
therefore, great care must be taken in this part of the work,
particularly for the composition for sky-rockets. When you have four
or five pounds of ingredients to mix, which is a sufficient quantity
at a time, (for a large proportion will not do so well,) first put the
different ingredients together, then work them about with your hands,
till you think they
are pretty well incorporated; after which, put
them into a lawn sieve with a receiver and top to it; and if, after it
is sifted, any remains that will not pass through the sieve, grind it
again till it is fine enough; and if it be twice sifted it will not be
amiss; but the compositions for wheels and common works are not so
material, nor need be so fine. But in all fixed works, from which the
fire is to play regular, the ingredients must be very fine, and great
care taken in mixing them well together; and observe, that in all
compositions wherein are iron filings, the hand must not touch them;
nor will any works which have iron or steel in their charge keep long
in damp weather.