Page:Popular Science Monthly Volume 8.djvu/138

128 increased fifty per cent. The Examiner, on the contrary, asserts that only by a reduction of fifty per cent. can the telegraph service be made self-sustaining. Such reduction, it is claimed, would have the same result as cheap postal rates.

experiments made on a large number of animals belonging to different orders, Rudolph Pott concludes that, of all animals, birds exhale the greatest amount, proportionately, of carbonic acid; after birds rank the mammalia, and then insects. Worms, amphibia, fishes, and snails, exhale much less carbonic acid than birds, mammals, or insects. The influence of age on carbonic-acid excretion is very marked: thus, for example, an old mouse exhaled in a given! time 3.873 grammes, a young one 4.349. But with insects the case is different, old individuals exhaling more carbonic acid than young.

Turkey, Russia, and Peru, the number of pupils receiving primary instruction in schools forms from $1⁄4$ to $1⁄2$ per cent, of the population; in Spain, 1 per cent.; in Italy, 6; in Hungary, $7 1⁄2$; in Austria, 9; in England and in Norway, 12; in France, 13; in Prussia, 15; in the United States; 17.

subjecting fishes to a pressure often atmospheres, Moreau found that the operation produced no injurious effects whatever. He then suddenly withdrew the pressure, and the fishes succumbed quickly from hæmorrhage, the blood having a frothy appearance. This phenomenon is due to the disengagement of the gases which, under the high pressure, had been taken up by the blood in great quantities.

is stated in Iron that De la Bastie's glass loses its molecular cohesion under a repetition of blows, and then breaks like common glass. Tempered glass, submitted to hammering, presents an appearance on fracture similar to that of fatigué steel, a molecular disintegration having taken place. It is feared that this alteration of structure and loss of temper may not only follow from shock, but may happen spontaneously from interior change in the lapse of time.

examination of the hull of the steamship Great Eastern showed a comparative absence of barnacles, though the stern-post, rudder, and screw were covered with them. The rest of that portion of the hull, which as a rule is below water, was clad with an enormous number of mussels, a surface of 52,000 feet being coated in parts to a depth of six inches. The total weight of the mussels is estimated at about 300 tons.

income of the French Association last year was 37,126 francs, and its capital fund now amounts to 174,731 francs. The Association gained 500 new members at its last meeting. Though the strictest economy must needs have been practised to accumulate so considerable a fund as 175,000 francs, nevertheless the material encouragement of scientific investigators is not neglected. Last year 12,350 francs were distributed for purposes of research.

batrachians of existing types have been regarded as of recent geological date—not earlier than the Tertiary epoch. Recently, however, batrachian remains were discovered in palæozoic rocks at Igornay (Saône-et-Loire), France. These remains have been described by A. Gaudry, who discovers in them affinities with the salamanders. Though the specimens appear to be adult, they are very small—a little over one inch in length. They occur in bituminous schists of the Permian age.

a substitute for the dredge in removing sand-banks and other deposits from rivers, a French engineer proposes to employ metal pipes pierced with holes; these pipes are inserted into the mass of the sand-bank and water driven through them at considerable pressure. In this way the sand and mud would be raised and agitated, and carried away by the current of the river or by the ebb-tide, if the operation were conducted at the ebb.

to Boillot, a French chemist, the bleaching effects usually attributed to chlorine are in reality due to ozone. Ozone employed directly acts as an oxidizing agent, laying hold of the hydrogen of the substance with which it is in contact, whence results bleaching if the body is colored. On allowing chlorine to act upon any animal or vegetable matter, it decomposes a certain quantity of water and seizes its hydrogen, forming hydrochloric acid. The oxygen set free by this reaction is transformed into ozone, which in its turn lays hold of hydrogen present in organic matter.

experiment in England has demonstrated the great advantages of the hammock system of conveying invalids by railway. The invalid suffers neither jar nor jolt. It is proposed to extend the benefits of the hammock system to the general traveling public, thus reducing the discomfort of railway-travel to the minimum.

cultivation of tea is making rapid progress in Ceylon, and extensive clearings of forest-land were made during the past year for forming new plantations. The seed is generally imported from India, though the Assam hybrid and China teas are also cultivated extensively.