Incubator

[U. Incubo.] An apparatus for the artificial hatching of eggs, heat being applied in¬ stead of the natural warmth of the body. Several hundred eggs may be hatched in a single incuba¬ tor. OF COMMON THINGS The hardened juice of several kinds of trees, It is also known by the names caoutchouc and elastic gum or resin. The india rubber of commerce comes chiefly from Mexico, South America, Madagascar, and the East Indies. The East Indian rubber is the juice of a kind of fig-tree, while the South American is that of the syringe-tree. A hole is made in the bark, and the juice is caught in a cup. It is pale yellow in color, and about as thick as cream, but when spread out it hardens and becomes nearly pure white. Previous to the beginning of this century india-rubber was used only for rubbing out pencil marks, but now its uses are very numerous. All kinds of elastic and waterproof goods are made from it. It is woven with silk, cotton, or woollen threads into a great number of fabrics. The discov¬ ery of the art of vulcanizing rubber by the addition of sulphur, which was made by Charles Good¬ year, an American, in 1839, has largely added to its uses. Tubes, fire-hose, and gas-pipes, elastic rings or bands, door and window springs, mats, boots and shoes, machinery belts, and many other useful things are made out of vulcanized rubber, which does not soften in hot weather like common rubber. Hard rubber or ebonite is made out of india-rubber and sulphur heated much hotter than vulcanized rubber. Canes, combs, backs of brushes, buttons, surgical instru¬ ments, picture-frames, knife handles, and a great variety of other things are made from ebonite. India-rubber mixed with sulphur and coal tar makes a substance so hard and black that it resembles jet. This may be cut and p dished and made into bracelets, breast-pins, sleeve buttons, studs, watch-guards, and other useful and ornamental things. Corn. (See Maize.) Summer. A term applied in the United States to the period of mild weather which nearly always conies at the close of October, extending sometimes to the middle of November. It is rainle and the atmospere is apt to be hazy. In Europe a similar season is known as St. Martin’s Summer. [U. indicum, from India.'] A well known and beautiful blue vegetable dye, obtained from the leaves of several species of plants which grow in the East and West Indies, India, Ceylon, Mexico, Brazil, Egypt, etc. Indigo is very extensively employed in dyeing and calico-print¬ ing. White indigo, discovered by Chevreul, results from the action of hydrogen on indigo. Indigo is made artificially in great quantities from cinnamic acid and isatin, which are derived from benzine. \n epidemic disease which comes suddenly, produces severe catarrh, and is very apt to develop into pneumonia or serious affec¬ tions of other parts of the body. In France it is known as la grippe, which name has become common, and many occurrences of it are upon record, one of the most persistent of which 659