2. Now with regard to SIEVES: you will require two of these, with
brass-wire bottoms; one of the fineness of twenty meshes to the inch for
_mixing_, which, for distinction’s sake, I will call _the mixer_; the
other of forty or fifty meshes to the inch for _sifting_, and to which I
shall refer as the _sifter_. These sieves are made with a receiver and a
top, so that by their means you can sift or mix any compositions,
however subtle or dusty may be their nature, without the slightest
inconvenience or annoyance. I may as well here mention that I use the
20-mesh mixer for _sifting_ the _coarse_ charcoal employed in my rocket
compositions, but all other sifting is done by the 40-mesh sifter. The
size of those which I use is about six inches in diameter, and I think
you will find this large enough for every purpose, as you will not be
likely to want to mix or sift any very large batches of composition at a
time. These sieves, made of any size or design that you please, may be
procured of Mr. Darby, 98, Regent Street, Lambeth, London, at whose shop
you will also find many other handy little articles, such as horn or
copper scoops, spatulas, &c.
[Illustration: Fig. 34. Fig. 35. Fig. 37. Fig. 38. Fig. 39. Fig. 40.
Fig. 44. Fig. 45. Fig. 46.]