256 



THE POPULAR SCIENCE MONTHLY. 



nance to sundry alloys, such as britannia 

 metal, pewter, etc., which commonly give 

 only a dull sound when struck. According 

 to the Engineering an</ Mining Journal, the 

 process consists in submitting articles made 

 of these alloys to the action of a certain 

 degree of temperature, just below their 

 melting-point, for a short time, in a bath of 

 oil or paraffine. The theory of the process 

 appears to turn upon a rearrangement, per- 

 haps a crystallization, of the molecules. 



The Phylloxera Commission, appointed 

 by the Paris Academy of Science, to award 

 the Government prize of 300,000 francs for 

 the discovery of an effectual means of de- 

 stroying the Phylloxera, has reported that 

 none of the specifics submitted to them are 

 entitled to the prize. 



Dr. Ewald records, in ReicherVs Archiv, 

 an instance of the production of a hydro- 

 carbon gas in the stomach of a man suffer- 

 ing from chronic gastritis. The man, one 

 day, while lighting a cigar, was surprised to 

 see his breath take fire, and burn with a 

 yellow flame. Dr. Ewald afterward analyzed 

 some of this gas, and found it to consist of 

 hydrogen, oxygen, nitrogen, carbonic acid, 

 and a considerable portion (about ten per 

 cent.) of marsh gas. 



About ten per cent, of the Cape dia- 

 monds are of first quality, fifteen per cent, 

 of second, twenty of third. The remain- 

 der are employed for cutting diamonds, and 

 for the numerous applications of this gem 

 in the arts. It is estimated that the value 

 of the diamonds found at the Cape from 

 March, 1867, to the present time exceeds 

 12,000,000. 



Dr. Richardson, of London, cites the 

 high death-rate of innkeepers, publicans, 

 and the like, as evidence of the fatal effects 

 of intoxicating drink. In London the mor- 

 tality of all males is 2.012 per cent, annu- 

 ally ; that of publicans, 3.466 per cent. In 

 England, exclusive of London, the mortality 

 of all males is 1.182 per cent, annually; of 

 publicans 3.163 per cent. It is a striking 

 fact that the death-rate in this class is high- 

 er than in any other class of male occupa- 

 tions named in the census, save one the 

 hackney-coachman. 



Salicylic acid has been used with good 

 results in (Jermany, in the treatment of re- 

 cent superficial gangrenous sores, the method 

 being to apply a thin layer of powdered 

 salicylic acid on the surface of the sore, 

 covering it then with wadding. 



Experiments lately made in France show 

 that air laden with coal-dust is highly ex- 

 plosive. Several cases of explosion in coal- 

 mines have been traced to the action of sus- 

 pended coal-dust when no fire-damp was 

 present. 



The practice of scalping is not peculiar 

 to the American aborigines. Southall, in 

 his " Recent Origin of Man," quotes from 

 Herodotus to show that the Scythians used 

 to scalp their fallen enemies. In the pres- 

 ent time the wild tribes of Northeastern 

 Bengal use the scalping^knife. 



An expedition under the leadership of 

 Prof. Nordenskiold will start next summer 

 to explore a commercial route from North- 

 ern Russia to Behring Strait. Funds have 

 also been contributed toward the cost of 

 another expedition to explore the gulf of 

 Obi and the sea-route between Archangel 

 and the great rivers of Siberia. 



Edmund A. Parkes, M. D., F. R. S., Pro- 

 fessor of Military Hygiene in the Army Medi- 

 cal School at Netley, England, died March 

 15th, at the age of fifty-six years. During 

 the Crimean War he was selected by Govern- 

 ment to organize and conduct a hospital, 

 and on bis return to England was appointed 

 to the chair of Hygiene at Netley. His 

 annual contributions on hygiene were for 

 many years, perhaps the most valuable feat- 

 ure of the blue-books of the War Depart- 

 ment. He was a very successful teacher, 

 and a frequent contributor to the medical 

 press, and to the " Transactions " of scientific 

 bodies. His " Manual of Practical Hygiene " 

 has reached a fourth edition. 



Died, March 29th, Dr. Henry Letheby, 

 for many years lecturer on chemistry and 

 toxicology in the London Hospital, and 

 chemical analyst of the city of London. He 

 was the author of a number of papers on 

 sanitary and chemical subjects, published in 

 sundry medical journals. His work on 

 "Food" was republished in this country 

 three years ago. At the time of his death 

 he was sixty years of age. 



Nearly all the amber of commerce comes 

 from Eastern Prussia, where it is obtained 

 by dredging the bottom of the sea .just off 

 the coast. It was recently discovered that 

 amber occurs in a deposit called the " blue 

 earth." It has been supposed that this 

 deposit extends for some distance inland, 

 and a shaft was recently sunk to determine 

 this point. At the depth of 140 feet there 

 was found a stratum of " blue earth " with- 

 out amber and two feet in thickness ; then 

 came another stratum five feet thick, which 

 was rich in amber. 



There are few who do not remember the 

 childish wonder they once felt at hearing 

 the resonance produced by placing a sea- 

 shell to the ear, an effect whicli fancy has 

 likened to "the roar of the sea." This is 

 caused by the hollow form of the shell and 

 its polished surface, enabling it to receive 

 and return the beatings of all sounds that 

 chance to be trembling in the air. Public 

 Opinion. 



