3^4 



THE POPULAR SCIENCE MONTHLY 



there were 53,195 deaths ; in 1871, 25,534 ; 

 in 1874, 12,026. That this decrease is due 

 to vaccination is shown from the fact that 

 in the northern districts, where vaccination 

 is in greater favor with the people than in 

 the southern, the rate of sinall-pox mortality 

 per 1,000 is 1.31, while in Umballa and six 

 other southern districts the rate is 2.05. 



The scientific results of the Polaris Ex- 

 pedition are nearly ready for publication. 

 They will form four volumes, the first three 

 of which, edited by Dr. Emil Bessels, will 

 be devoted to hydrography, meteorology, 

 aud astronomy. The fourth volume, of 

 which Admiral Davis has charge, will con- 

 tain a narrative of the expedition and much 

 biographical information. 



A new industry has been introduced in 

 France the breeding of ants for their eggs. 

 These eggs are sold to the breeders of 

 pheasants. As yet the business is in the 

 hands of its originator, a woman, and she 

 already appears to be on the high-road to 

 fortune. 



From experiments made by Scolosuboff, 

 it appears that dogs can absorb with im- 

 punity about sixteen times as much arsenic 

 (in proportion to their weight) as would 

 kill a human being. 



The cinchona-tree has been introduced 

 successfully into the island of Reunion. 

 The cinchona-seeds were first sowed near 

 the coast, and the young trees which grew 

 from them were subsequently conveyed to 

 an altitude of from 2,000 to 2,500 feet. 

 There they thrive so well that in four years' 

 time some of them grew to the height of 

 twenty-one feet. 



In the annual report of Prof. Henry it 

 is stated that the Smithsonian Institution 

 fund now amounts to $71*7,000. It is con- 

 templated to authorize a series of experi- 

 ments to determine accurately the rate of 

 increase of the earth's temperature at pro- 

 gressive depths. Another project embraces 

 new and careful experiments on the velocity 

 of light. The work of ascertaining the 

 weight of the earth by Cavendish's method 

 will also probably be undertaken anew. 



In the milk of cows affected by the foot 

 and mouth disease, there is a marked ten- 

 dency of the fit-globules to aggregate. The 

 latter are also much larger than in healthy 

 milk, and in advanced stages of the disease 

 rise to the surface, not as cream, but as 

 pure butter-fat. The film enveloping the 

 particles of fat presents a glairy, mucus-like 

 appearance, and is intensely refractive. It 

 is only necessary to agitate a strongly-af- 

 fected sample of the milk for a few minutes 

 in order to obtain from a pint of milk a 

 lump of butter weighing au ounce or more. 



German manufacturers are purchasing 

 the fish-bones gathered along the Norwegian 

 coast at the great fish-curing stations. The 

 bones make a good fertilizer, and when pul- 

 verized by suitable machinery at the point 

 of collection are readily transported. It is 

 estimated that the bone-product of the es- 

 tablishments in Newfoundland amount to 

 20,000,000 pounds a year. 



Dr. R. Angus Smith advocates the cult- 

 ure of peat as a fuel. In the Grampian 

 Hills he finds a bog, the annual product of 

 which is ten tons of dry peat equal to four 

 tons of coal. By proper treatment it is 

 possible to grow the material much faster 

 than this. Indeed, the product of the bog 

 mentioned above is considered to be far be- 

 low the average. 



Explosions of fire-damp in coal-mines 

 are found to occur most numerously in times 

 of low atmospheric pressure. When the 

 pressure is great, the carburetted hydrogen 

 is prevented from issuing from the walls and 

 sides of the coal-seam ; but when the press- 

 ure is suddenly lessened the gas escapes, 

 and accumulates until sometimes it reaches 

 the proportion sufficient with common air 

 to form an explosive mixture. 



Mr. Henry S. Drinker, of Philadelphia, 

 mining engineer, is preparing a work on 

 "American Tunnels and Tunneling," and 

 has sent out a circular in which he requests 

 that data concerning railroad tunnels, min- 

 ing tunnels, headings, and drifts, be for- 

 warded to him, so as to make the work as 

 complete as possible. Mr. Drinker's ad- 

 dress is 1,906 Pine Street, Philadelphia. 



Applying to the elephant Flourens's 

 mode of estimating the natural duration of 

 an animal's life, viz., multiplying by five the 

 number of years requisite to perfect its 

 growth and development, Sir J. Emerson 

 Tennent fixes the terra of life for that great 

 pachyderm at (thirty by five) a hundred and 

 fifty years. Maturity is shown by the con- 

 solidation of the bones of the animal with 

 the epiphyses, and in the elephant this con- 

 solidation is complete at the age of about 

 thirty. 



In the seal-fishery an enormous amount 

 of wholesome meat is annually wasted. Only 

 the blubber and skins of the seals are brought 

 away. It is proposed to have the meat put 

 up in tin cans at Disco, and so shipped to 

 Europe for food. 



A movement is on foot to bring about a 

 uniformity of measures, instruments, and 

 methods of observation, among physicians 

 in all countries. It is proposed to ask the 

 next International Medical Congress to con- 

 stitute national commissions for the purpose 

 of deciding upon the most practical means 

 of attaining this object. 



