Page:Popular Science Monthly Volume 47.djvu/735

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.

congress was divided for convenience into two sections, one dealing with educational and the other with mathematical geography. Most of the prominent geographers of the world were present, and much valuable work was done. The visitors were entertained in royal style, and the social features were not the least attractive part of the meeting.

The yellow coloration of milk on exposure to heat is due, according to M. Cazeneuve and M. Haddon, to the oxidation of the lactose in presence of the alkaline salts of the milk. Lactose during this oxidation yields acids, especially formic acid, easily detected, the presence of which suffices to explain the coagulation of the milk as it ensues with any acid.

The French Association for the Advancement of Science will meet at Bordeaux, from August 4th to August 9th, under the presidency of M. E. Trelat.

Three cases of tuberculosis following tattooing are reported in the British Medical Journal. Three boys were tattooed by the same woman, who used her saliva as a vehicle for the coloring matter. The woman died soon afterward with pulmonary tuberculosis, and all the boys presented unmistakable signs of tuberculosis at the site of the operation.

Bacteriology has taken up the telephone as a disseminator of disease, and may make necessary the adoption of some device by which the danger of infection from the mouthpiece, which many people allow to touch the lips, can be avoided. The medical journals of Paris are agitating the matter.

The ultra-conservatism which is so certainly bred by life about an old university was sadly illustrated recently at Oxford by the rejection of a proposal to include anthropology among the subjects of the final school of natural science not as an extra but as an equivalent subject. There axe unfortunately still in high positions classical teachers who believe that science is an unessential part of a nineteenth-century education.

Rather a novel contrivance for utilizing air currents in irrigation is described in the Louisiana Planter. "A crude invention, which is called the 'Jumbo' wind engine, appeared in western Kansas about ten years ago, and is now coming into extensive use. It resembles the paddle wheel of a stern wheel boat, with a shaft twelve or fourteen feet long, with a diameter of twelve or sixteen feet, with six or eight radial arms. The lower half of this horizontal wheel is shielded from the wind, so that the air acts only upon the upper vanes. A crank upon one end of the shaft connects with a pump. Its power can be indefinitely increased by increasing its length. It is said that a Jumbo giving one hundred horse power in a fifteen-mile wind can be put up at a cost of five hundred dollars. The wind acts on this sort of paddle wheel from all points of the compass except two."

The recorded heights of what are called maximum waves on the ocean vary from forty feet from crest to hollow to ninety feet. The great storm waves travel very far and faster than the storms, so that preceding them they give warning of them. Sometimes they appear as a record of a far-away storm that is spent. When they have traveled beyond the limits of the wind that raised them they become long undulations, hardly noticed in deep water, but very evident in shallow places. These probably form the "rollers" that appear periodically in places situated in latitudes where gales do not occur. Other rollers are believed by Captain W. J. L. Wharton to be due to earthquakes or volcanic eruptions occurring in the bed of the sea. Of these are the sudden great waves which often cause so much destruction on the South American coasts.

A marked decrease in the killed and injured among railroad employees in 1894 is attributed in the report of the Interstate Commerce Commission to the smaller number of men, the smaller volume of business transacted, and perhaps to the increased use of automatic appliances and the improved grade of efficiency of the men. One man was killed out of every 428 in service, and one injured out of every 23. One passenger was killed out of each 1,912,618 carried, or for each 44,103,228 miles traveled; and one injured out of each 204,248 carried, or for each 4,709,77l miles traveled. A distribution of accidents to the terminal groups into which the railroads are divided exhibits the diversity in the relative safety of railway employment and of railway travel in the different sections of the country.

The Reichsbank, the German Government's banking establishment recently made some instructive experiments, with cement as a fireproof covering for safes. A safe consisting of steel wire netting, between two layers of cement, was subjected to a heat of 1,800º F. for over half an hour. When the safe was opened, silk paper was found uninjured, and a maximum thermometer, which had been in the safe, had only registered 85º F.

Some interesting observations on the relation of dust to rainfall and scenic effect were made during a trip to Greenland last summer by Prof. William H. Brewer, of the Sheffield Scientific School. He says that the fogs progressively thinned as they went farther north; that, owing to the small amount of dust in the air, the rain, even when streams were flowing from the scuppers,