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284 applications. Borax and boric acid, which are included in the four receipts here given, are very fusible, and are not changed by heat, but only by an excess of moisture in the air, and well fulfill the first condition. Hydrochlorate, carbonate, and sulphate of ammonia readily give off incombustible gases, which have also the positive quality of extinguishing combustion, and thus admirably fulfill the other condition. Hence the compositions recommended possess all the desired qualities. They have also responded satisfactorily to varied tests of experiment.

A New African Region.—The Rev. David Asante, a native missionary of the Basle Gold Coast mission, Africa, recently visited during a journey of exploration the hill-country of Booso, where he says the temperature is cool, rains are frequent, and rivulets numerous. The country is thinly peopled by a population subject to goitre and extremely dirty, whose children and bachelors wear no clothing. Wives, being harder to get—by the process of wooing and winning their consent—than in most African countries are treated well. The fetich-worship is less subtile than on the coast, but the poison-ordeal is frequently resorted to, and accounts for the small population. When a person dies, a whole village sometimes submits to take an infusion of a poisonous bark. Quarrels are settled by resorting to the same dangerous arbiter, thefts are discovered by it, babies who cry much are made to swallow the infusion to prevent their growing up wicked, and parents who lose several children in succession take it in order that the cause of their affliction may be discovered.

Petroleum Products as Fuel.—The residues of the distillation of petroleum have been employed in the Caucasus for several years as a combustible, and have appreciated from having no value in 1874 till they command a price six times higher than crude naphtha, which is now employed as a cheaper fuel. Naphtha has been considered dangerous on account of its explosive qualities, but it has been found that they disappear when the liquid has been exposed to the air for a few days till it has lost its volatile constituents, which compose about fifteen per cent of its substance. Crude naphtha, right from the springs, is burned in the locomotive-furnaces of the Balachanskoi rail-road, and there are no accidents. Naphtha is the fuel that develops the greatest quantity of heat, and it also possesses the great advantage of not containing sulphur or other injurious substances. Ninety per cent of the theoretic calorific power can be realized from it, while not more than sixty per cent can be got from solid combustibles. In 1859, doubts were expressed in Russia as to whether petroleum could be used as a combustible; now it is employed exclusively on all the ships in the Caspian Sea, and only half as much of it is required as used to be consumed of coal. The maximum force to be obtained from petroleum is equivalent to two and a half times what coal will furnish; and experiments on the railroad from Baku to Balachan show that a given weight of naphtha will take the place of eight and a half times the weight of wood, although the theoretically calculated difference in calorific power is only as three to one. Petroleum is very conveniently introduced into the furnaces of locomotives with the injectors that are used; the combustion is very easily regulated, and the furnaces last well in the absence of sulphur, while no smoke, sparks, or ashes, are emitted.

Make Room for City Children.—Dr. James B. Russell, health-officer of Glasgow, while he admits that the moral delinquencies of parents, and particularly drunkenness, are important factors to the death-rate of children in cities, insists that too much influence should not be attributed to them. The child of sober, industrious parents, in a city of good sanitary conditions, still lacks room for his complete well-being. The element of space comprehends all the physical conditions of health so completely that the name density is recognized by vital statisticians as the best standard of comparative measurement. Then, as the child grows up, comes the natural desire for play and exercise, which is essential for health and growth. Pent up as city children are, their play becomes in great part mischief. The prevailing characteristics of children's play correspond with the manners, habits, and