Now there is also an artificial camphor for fireworks, which I shall here give you the method of making; take of gum sandarach pulverised two pound, and of distilled vinegar enough to cover it; put them together in a glass phial, and set it for twenty days in warm horse dung. Then take it out again, and pour it into another phial, with a large mouth to it; and expose it to the sun for a month, and you will have a concreted camphor in form of the crust of bread, and something like the natural camphor: which when you use must be ground to a powder with a little spirits of wine in a mortar. Though we have here taught the method of making artificial camphor, I would not recommend it to those who chuse to make their works to perfection, the natural camphor, being by far the best. To make the OIL of CAMPHOR. The oil of camphor, which is sometime used to moisten compositions, is produced by adding to some camphor a little oil of sweet almonds, and working them together in a brass mortar, till it turns to a green oil. N. B. Those works that have any camphor in their compositions, should be kept as much from air as possible, or the camphor will evaporate. Of BENJAMIN. Benjamin is a resin (much used by perfumers, and sometimes in medicine); it is brought from the Indies, where it is found of different sorts; and distinguished by the following colours, viz. yellow, grey, and brown, but the best is that which is easy to break and full of white spots. Benjamin is also one of the ingredients in odoriferous fireworks, when reduced to a fine flour; which may be done by observing the following directions. Put into a deep, and narrow earthen pot, three or four ounces of benjamin grossly pounded, cover the pot with paper, which tie very close round the edge; then set the pot on a slow fire, and once in an hour take off the paper, and you will find some flower sticking to it, which return again in the pot; this you must continue till the flower appears white and fine. There is also an oil of benjamin, which is sometimes drawn from the dregs of the flour; it affords a very good scent, and may be used in wet compositions. Of GUN-POWDER and its original.