446 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



recognized in it simply a dilute peroxide of hydrogen, pre- 

 pared with well-water, and which owes its permanence to 

 the great degree of dilution and the presence of a small 

 quantity of free acid, most probably nitric acid. 9 G, Decem- 

 ber, 1874, 183. 



DUST -SPECTACLES FOR THE PROTECTION OF THE EYES IN 



VARIOUS OCCUPATIONS. 



Spectacle frames, furnished with fine wire gauze instead of 

 glass, carefully fitted to the eye, and fastened to the head by 

 a gum band, have been found by Kiihn to answer perfectly 

 for the protection of the eyes from dust, solid particles, etc., 

 in various occupations, as threshing, stone-cutting, etc., while 

 they at the same time permit the necessary access of air to 

 the eye, and produce no inconvenience whatever to the wear- 

 er. 15 (7, XVIL, 1874, 266. 



PRESERVATION OF MEAT, VEGETABLES, ETC., BY ACETATE OF 



AMMONIA. 



According to an English patent, fresh meat, fish, vegetables, 

 etc., are preserved by immersing them in a more or less con- 

 centrated solution of acetate of ammonia, and allowing them 

 to dry in the air. If the articles are to be preserved for 

 months or years, they are packed in cans or casks filled with 

 a solution of the salt. The boiling, roasting, etc., readily 

 expels the acetate, and the articles are said to be free from 

 the sweetish taste which acetate of soda imparts. 5 (7, L., 

 1874,400. 



PREVENTING THE CURDLING OF MILK BY OIL OF MUSTARD. 



The observation of Schalbe, that the addition of a single 

 drop of oil of mustard to 30 grains of milk will prevent its 

 curdling, for weeks, has been fully confirmed by Yogel in ex- 

 haustive comparative experiments with fresh milk, with and 

 "without oil of mustard, including the determination, from 

 time to time, of the amount of lactic acid present; from 

 which it also appears that this effect of oil of mustard is due 

 to a retarding action upon the formation of lactic acid, its 

 formation being also almost entirely prevented during the 

 first eleven days, and the amount present fourteen days later 

 being only one seventh of that in milk not so treated. Oil 



