The manufacture is very simple: the lead is first tempered by the aid of arsenic, in the proportions required by the slag (a technical term) for the kind used; some lead taking more and some less. The melted metal is then poured into a perforated pan placed over the mouth of the pit, or tower (whichever may be in use.) Messrs. Walkers, Parkers, and Co. have towers in their various factories where they make shot; the cut represents the one in Newcastle. Messrs. Locke, Blackett, and Co. cast down the shaft of a pit, and by this means obtain a greater fall. The fluid metal takes a globular shape in falling, and the concentric motion of each particle round its axis keeps it in this form until its passage through the air has extracted the heat, and before it reaches the body of water placed to receive it. The only difficulty is in casting very large sizes; for if the distance the drops fall be not sufficiently great, and they reach the water in a semi-fluid state, the resistance of the water misshapes them. About three different sizes come out through one pan. These are separated by the aid of riddles, or tabled, as the process is termed. A quantity of the shot is placed on a slight incline, when those that do not run off are rejected. The whole are then polished in a machine termed a drum, with a mixture of black lead. This gives to the shot that beautiful polish which captivates the eye, but which injures the shooting of the gun, as the black lead adheres to the interior of the tube. All shot should be used unpolished; and the addition of hardness is unquestionably another advantage. Slag-lead is lighter than other lead, but it is much harder, and thus more suitable for shot. I regret the disuse of shot made with quicksilver, as it is unquestionably much superior, though more costly. A considerable improvement is yet to be introduced in the manipulation of shot-making; and I shall commence a round of experiments with that object at the earliest opportunity. Copper caps are now a misnomer: very few are to be met with. Brass caps boiled to the colour of copper are the rule, the former the exception. Good caps are made in Birmingham, if a remunerative price is paid for them; and I have the pleasure to name several makers: Messrs. E. and A. Ludlow, Messrs. Pursall and Philips, and Mr. Cox. It must be borne in mind that cheapness means inferiority: every article is made according to price. The mixture of fulminating mercury composition is: Fulminating mercury 3 grains or ounces. Chlorate of potash 5 do. Sulphur 1 do. Powdered glass 1 do. The above is one of the best compounds in use. Chlorate of Potash 6 grains or ounces. Sulphur 3 do. Glass, powdered 1 do. Charcoal, ditto 1/2 do. Is the best mixture where the corrosive principle is not heeded.