Coloring for Tooth Powder, etc.—An unobjectionable color for tooth powder can be made by dissolving 1 oz. of the best carmine in 6 fluid-ounces of stronger solution of ammonia, and adding this to a portion of the precipitated chalk in a large mortar, using sufficient quantity to absorb the liquid. This is triturated with more of the carbonate of calcium until enough is added to bring it to the state of powder. This is then allowed to dry, and, when free from the smell of ammonia, mixed with the other ingredients of which the dentrifice is composed. The quantities given are sufficient to give a brilliant pink tint to thirteen pounds of tooth powder. By making a solution of carmine in ammonia a more thorough diffusion of color is effected, and 1 oz. of carmine used in this way will be equal to about one and three quarter ounce when used as a powder.
Cleaning Mortars, Slabs, etc.—Mortars in which oil, balsam or grease have been mixed should first be thoroughly scraped with a spatula, then wiped out with paper, next with a piece of cotton batting slightly moistened with spirits of turpentine, and, lastly, with cotton moistened with a little soap liniment, and washed with water. By this treatment tar, oil, grease, petroleum, balsams, iodoform, asafoetida and resins can be effectually removed and much time and annoyance saved. Stains from iodine are best removed by rubbing a few grains of iodide of potassium and a very small quantity of water together, which forms a concentrated solution in which iodine is soluble. For permanganate of potassium stain use muriatic acid. Indigo will be removed by strong sulphuric acid.
Chinese White Wax.—From an article in the "British Mail" on the white wax industry of China, it seems that the average annual value of this peculiar crop amounts to about £650,000. From Han-kow alone upwards of £81,000 worth of this wax was exported in 1879. The Chinese white wax is a deposit found on twigs of Ligustrum lucidum, and caused by the puncture of an insect. It is said that in Keenchang district the plant thrives in great abundance, and in the spring of the year the twigs are covered with countless swarms of flies having the appearance of a brown film. The branches soon became covered with a white soap-like incrustation, which increases in volume till the commencement of the fall of the year, when the sprays are cut off and immersed in water which is kept boiling. The viscid substance rises to the surface, and is skimmed off, melted and allowed to cool in deep pans. It was accidentally discovered that, by transporting the insects from their native districts to the more vigorous one of Keating-fu, in the north of the province, their power of discharging wax was largely augmented—a property which was promptly and extensively availed of by the Sze-chuen traders. The period between evening and morning is chosen for conveyance, because many hours of sunlight would precipitate the hatching. This should take place only after the females have been attached to the trees. Arrived at their destination, six or more of the mothers—which are enormously prolific—are tied, wrapped in a palm leaf, to a branch of the ligustrum. A few days later the young flies are swarming on the twigs, where they fulfill their mission by the month of August; then they perish in the cauldrons, where the results are immediately collected. It is stated that this peculiar industry requires the exercise of great care and forethought.—Pharm. Jour. and Trans., Oct. 16, 1880, from the Gardeners' Chronicle, Oct. 2, 1880.