Page:Popular Science Monthly Volume 39.djvu/290

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THE POPULAR SCIENCE MONTHLY.

the Negritos into the Sakai and the Samang. The Sakai are a people of moderate stature and large bones, fairer in complexion than the Malays, with long, wavy hair standing straight out from their heads. The Samang are small and dark, with black, frizzy hair close to their heads, like that of the negro races. Some writers have inferred, from comparison of languages, that there are connecting links between the Negritos of various tribes and the Malays, and believe that the former show traces of Melanesian blood.

Massage in Ancient Times.—Massage has apparently been practiced from the very earliest times. A Chinese manuscript of three thousand years before the Christian era contains an account of operations very similar to those which go under that name at the present time—friction, kneading, manipulating, and rolling. A form of massage was the common accompaniment of the bath with the Egyptians, Greeks, and Romans, and was used as a luxury, a means of hastening tedious convalescence, and of making the limbs supple and enduring. Hippocrates commended it; Esculapius believed in it; Cicero affirmed that he owed as much of his health to his anointer as he did to his physician; Julius Cæsar had himself pinched all over every day for neuralgia; and Pliny enjoyed great benefit from it. Celsus advised rubbing to be applied to the whole body; and the works of Plato abound in references to the use of friction. Peter Henrik Ling is said to have based the Swedish movementcure on the Chinese Kong-Fan manuscript. Lepage relates that the Chinese massage was a particular practice borrowed from the Indians, and that it was by such means that the Brahmans effected their miraculous cures. The method is common among the Polynesians, and something like it was found among the Australians.

Decay of India Rubber.—Mr. W. Thomson says, in a paper on the vulcanization and decay of India rubber, that copper salts have an injurious effect on India rubber, and, as that metal is sometimes used in dyeing blacks and other colors, cloth so dyed is liable to decompose and harden the rubber put into it. Metallic copper placed in contact with thin sheets of India rubber brings about oxidation and hardening of its substance, although no appreciable quantity of copper enters the India rubber; but metallic zinc and silver have no injurious effect on the rubber. The author had found that if oil containing a certain amount of copper, which it often does, gets on the clothe the action of the bleaching agents on the copper damages the cloth. There is an acid in ordinary linseed oil that rots cloth. The smell of India rubber is one of the characteristics of its decomposition. When a piece of blotting-paper is placed over decaying rubber, it becomes colored by some of the emanations, as does not occur with good rubber. There is therefore no doubt that certain volatile substances are emitted during the oxidation that produces the hardening of India rubber. Rubber can be kept best under water or glycerin, or in coal-gas. It remained good when placed in a vacuum and exposed to sunlight for twelve months. All oils, except castor oil, have a detrimental effect on India rubber.

Cancer and Nervous Disease.—In an article in the Nineteenth Century, Mr. Herbert Snow shows that mortality from cancer in the United Kingdom is increasing at an accelerating rate, and that the disease is of nervous origin. According to the Registrar-General's returns, the aggregate mortality from this disease in England and Wales has grown, during the twenty-five years 1864-1888, from 8,111 to 17,506 a year. In proof that the increase in mortality can not be adequately accounted for by the growth of population, the tables are again invoked to show that the mortality from cancer per million persons living has risen during the same period from 385 to 610. The increase, year by year, has been very regular. Returns of a like character from Ireland and Scotland tell the same story. Dr. Fordyce Barker is quoted as having shown that the number of deaths per million in New York rose from 400 in 1875 to 530 in 1885. Cancer may be and often is initiated by direct mechanical injury or irritation; "but in by far the larger proportion of those varieties of cancer which furnish the bulk of the mortality statistics no such mechanical exciting cause can be detected." Moreover, as no additional liability to local injury or