Page:Popular Science Monthly Volume 12.djvu/782

This page has been validated.
762
THE POPULAR SCIENCE MONTHLY.

ing over the shoulders and attached to the poles by ropes. These ropes are so adjusted that when the men stand still, and the chair is loaded, the poles are bent about three inches. In carrying, the easy swing of the ordinary chair is lost, for, just as the Formosan chair is coming down gently, it is brought up short by the men close to it. The motion is exactly the same as is used for jigging crushed metallic ores.

 

Chinese Medicines.—The Chinese pharmacopœia contains instructions for preparing sundry very curious medicines, as, for instance, various animal "wines"—mutton wine, dog-wine, deer-wine, tiger-bone wine, snake-wine, tortoise-wine, and so on. These "wines" (chiu) are employed instead of alcohol as a solvent for articles used as medicines. The mode of preparing mutton-wine is described as follows by Dr. D. J. Macgowan, of Shanghai: The ingredients are one sheep, forty catties (a catty equals 113 pound) of cow's-milk wine, a pint of sour skimmed milk, eight ounces brown sugar, four ounces honey, four ounces fruit of dinocarpus, one catty raisins, and about one catty of half a dozen other drugs. The utensils employed are a large cast-iron pot, a wooden barrel (boorher) about two feet high, and tapering, open at both ends, a smaller iron pot, an earthenware jar; felt belts and cow-dung are used for making the apparatus air-tight. The boorher is set on the large pot, the joining being first calked with paper, and then daubed on the outside with cow-dung and ashes; the boorher, too, is made air-tight in the same way. Then pour in the wine, add half the raisins, cut or crushed, half the sugar, the milk, and the bones of the sheep's legs, from the knees down, after breaking them open. From the other bones strip all the fat and most of the flesh, and hang them inside the boorher beyond the reach of the wine. Put in the medicines, the honey, and the remainder of the sugar and raisins. The earthenware jar is then suspended in the centre of the boorher, and the smaller iron pot is set on top, the joint being made air-tight by paper, cloth, and felt bands. A fire is now made under the great pot; when the upper pot feels warm to the touch, fill it with cold water. When this water is too hot to touch, it is ladled out, and the pot filled again with cold water. When this in turn becomes hot, the fire is slackened, the upper pot taken off, and the earthenware pot, which is now found to be full of a dirty brown liquor, is taken out, the liquid poured off, the vessel replaced, and the upper pot, filled with cold water, again set upon the top of the boorher. When the water on top is again heated, the whole operation is completed. The earthenware pot is now again found to be about half full, and its contents are poured off, allowed to cool, and put up in jars.

 

Utilization of Blast-Furnace Slag.—Within a few years great progress has been made in the utilization of blast-furnace slag, and that material is now applied in many ways with great advantage. Thus, slag "sand" is employed for making concrete, building-bricks, mortar, and cement; slag "shingle" for concrete, also for roadways; slag "wool" for covering steam-boilers and pipes, ice-houses, etc., also for filtering-purposes; blocks of slag-concrete are used for paving, for curbstones and the like; finally, by Britten's process, slag is used in the manufacture of glass for roofing, and for other purposes not requiring pure glass. In making building-bricks of slag, the slag-sand is mixed with selenitic lime, with the addition of iron oxide, and pressed in moulds. The cement is made from the slag-sand, common lime, and iron oxides. It is little inferior to Portland cement in strength, while it does not cost one-fourth as much. The concrete made from this cement, mixed with the "shingle," is an excellent conglomerate for use in monolithic structures. It is stated by Mr. Charles Wood, in a paper read before the British Iron and Steel Institute, that "it took two good men, with steel bars and sledge-hammers, as much as four days to cut through a wall of this concrete about twenty-six inches thick." Mr. Wood exhibited to the Institute bottles of slag-glass, also specimens of slag-wool. The latter product, according to Mr. Wood, is obtained as follows: A jet of steam is made to strike a stream of molten slag as it falls into the slag-bogies or wagons. This jet scatters the molten slag into shot, and as each shot leaves the stream it carries a fine