[N] In this country, powdered arsenic is almost exclusively used by preparors--and is alone sufficient for this purpose--the arsenical soap is not sufficiently strong; no fatal effects have been known to follow its use; care should be taken to wash frequently.--_Tr._ The preparor Nicholas recommends, in certain cases, a composition which ought to be here mentioned, not to advise the use of it, on the contrary, to advise the rejection of it; for far from driving off the insects, it attracts them; he calls it _gummy paste_. ℞. Colocynth, 2 ℥. Gum Arabic, 4 ℥. Amidon, 6 ℥. Cotton, hashed fine, 1 ℥. Other preparors, without passing any thing over the skin, confine themselves to the use of the following powder: ℞. Calcined alum, 3 ℥. Flour of sulphur, 1 ℥. Black pepper, 1/2 ℥. Powdered tobacco, 1/2 ℥. Powdered sabine, 1/2 ℥. Powdered camphor, 3 ʒ. The whole to be finely powdered and well mixed. Some amateurs content themselves in passing over the internal surface of the skin they wish to preserve, a good layer of melted suet mixed with a small quantity of corrosive sublimate; it appears that they have obtained some advantageous results, which authorises further experiments; it has been remarked, that suet is never attacked by insects; perhaps, if it were combined with some mineral matter less dangerous than the sublimate, results as satisfactory as those from the arsenical soap of Bècoeur might be obtained. Such are the preservatives which have been employed in France, but which do not possess, to any extent, the efficacy of the arsenical soap of Bècoeur. It appears that the Germans employ others to which they attribute the same qualities, which appears to us very doubtful in all cases: they may be mentioned here. Naumann, in the first place, gives a method which appears to us vicious, although he invokes in its favour his own experience. After having said that the best method of preserving is to close hermetically, stuffed animals in boxes, he adds: “I do no more for skins which are to travel in boxes, than powder them with the following composition: “Of lime decomposed in the air, and finely sifted, two parts; of saxony tobacco, also sifted, one part.” Hoffman approves of, and recommends the following powder: ℞. Sal ammoniac, 1 ℥. Calcined alum, 1/2 ℥. Saxony tobacco, 3 ℥. Aloes, 1 ʒ. The librarian of Jena, M. Theodore Thon, proposes the following powder, as better for preserving animals in the open air.