6336. To Transfer Engravings on Wood, Stone, etc.

6336.      To Transfer Engravings on Wood, Stone, etc.. Take a saturated alcoholic solution of potash, pour the solution on the engraving, and immediately remove all the superfluous liquid by means of blotting paper. Lay the engraving, while damp, upon tho wood or other material to which it is to be transferred, and place it in a press. (A copper-plate press is tho best.) The transfer will be obtained immediately. The engraving must be immersed in clear, cold water, after removal from the potash bath. (Orr.)

6337. How to Wash Printing Rollers

6337.   How to Wash Printing Rollers. Avoid all grit, sand, and dirt; simply use strong ley to loosen the ink, and quickly, with a soft sponge, wash the ley off with water (in winter blood-warm) squeezing the sponge dry, face up the roller, so that no moisture remain there on. Let it then stand exposed to tho air one hour, machine rollers two hours, before distributing ink on its surface. The time for exposure must be guided by the state of the weather, as shorter time will do in dry or windy weather. Be careful to ink the roller as soon as possible after exposure, to keep it tacky. (Sec No. 2542.)

6338. Gelatine Capsules

6338.    Gelatine Capsules. A strong solution is made of 6 parts gelatine and 1 part sugar; the extremity of a rod of bulbous shape is oiled, and dipped into the solution; when the rod is withdrawn it is rotated, in order to diffuse the fluid jelly equally over its surface; as soon as the gelatinous film has partially hardened, it is removed from the mould and placed on pins furnished with suitable heads, and fixed on a cork table. When dry, the capsules are placed upright in little cells made in the table to receive them, and the liquid with which they are to be filled is introduced by means of a small glass tube. They are then closed by dropping some melted gelatine on the orifice of each. Ricord recommends that capsules containing copaiba be coated with extract of rhatany, which is easily done by immersing the capsule for an instant in a mixture of 3 parts newly prepared extract of rhatany, 1 part syrup of moist sugar, and 1 part mucilage of gum ara-bic, melted together in a water-bath. Capsules thus prepared are said to act with greater certainty, as well as improving the tone of the stomach.

6339. To Remove Nitrate of Silver Stains

6339.    To Remove Nitrate of Silver Stains. A solution of iodide of potassium will freely dissolve iodine. Silver stains moistened for a while with this solution will be converted into iodide of silver, which is soluble in iodide of potassium. The stains will therefore have disappeared when the cloth, after the foregoing treatment, is washed in water. (See No. 385 (To Remove Stains made by Hair Dye, or Indelible Ink).) Perhaps the best method of removing these stains is as follows: The stained cloth is washed with a concentrated solution of sulphate or chloride of zinc and then touched with a piece of metallic zinc. This same process may be used for the removal of ink stains in both cases without danger to the fabric. After the color has disappeared, they are washed first with pure water and then with water and soap. No visible traces of the stains are left behind. (See No. 3141 (To Remove Nitrate of Silver Stains).)