210 ANNUAL OF SCIENTIFIC DISCOVERY. 



It is pulverized and mixed with sulphuric acid, then heated in an 

 oven to eliminate the hydrated silica, the residuum treated with 

 boiling water, and made to crystallize. 



A Curious Chemical Observation. Becquerel, senior, has found 

 that chemical decomposition and combination take place actively, 

 and with peculiar results, between two solutions connected by an 

 inappreciable fissure, or water-tight joint. A tube with such a 

 fissure in its bottom, being filled with a solution of nitrate of cop- 

 per, none of the liquid pours mechanically ; but on immersing the 

 bottom of the tube in liquid proto-sulphuret of sodium, an electri- 

 cal action takes place, and a double decomposition and recompo- 

 sition ensues, indicated by the appearance of crystals on both 

 sides of the fissure, which are not always of the nature required 

 by theory, but are modified by the capillary action of the sur- 

 faces. 



Oxygen in the Market. A company has been formed in Paris, 

 under the style of Jos. de Susini & Co., for the manufacture and 

 sale of oxygen to be mixed with ordinary illuminating gases. The 

 calculation is that an addition of one-third oxygen will be equiva- 

 lent to multiplying a given quantity of illuminating gas 8 times, 

 the price of oxygen being fixed at only 2 times that of ordinary 

 gas. 



Ozone. In an English patent, issued some time since, for de- 

 colorizing sugar by means of ozone, the generator employed for 

 the purpose consists of a number of flat sheets of glass, coated 

 with tin-foil, and piled one on the other, but slightly separated. 

 Each plate represents a Leyden jar, and when the whole number 

 are electrified, a stream of air forced through from one end to the 

 other becomes so strongly ozonized that breathing it is painful and 

 dangerous. The stream of ozonized air thus produced can be used 

 for bleaching and other chemical purposes. 



Cinnabar. Cinnabar of a beautiful vermilion color is found in 

 an unusual form in Idaho, being abundantly spread throughout a 

 gangue so massive, compact, and homogeneous, that specimens 

 may be cut and polished like marble. 



Sulphurous Acid. This may be produced on the large scale by 

 heating together 2 parts of dry sulphate of iron and 1 part of 

 sulphur ; the reaction is Fe O, So 3 -|- 2S = Fe S -f- 2SO 2 . 



Treatment of Gelatine and Gum. A useful invention, capable of 

 wide application, has recently been patented in England. It con- 

 sists in the use of sulphate of sesquioxide of chromium, or chrome 

 alum, for rendering gelatine or gum (Senegal or Arabic) insoluble 

 in water. It is applicable to the fixing of dies and pigments for 

 textile fabrics ; to the tanning of skins ; to the fixing of photo- 

 graphs and prints produced in gelatinous ink; and to the prepara- 

 tion of insoluble varnishes. 



Paper wliicli turns Pale Ink instantly Slack. This is effected by 

 introducing into the glazing a neutral carbonate which effects a 

 prompt oxidation of the ink without injuring the paper. It is 

 called by Mr. J. E. Hover, its inventor, carbonized paper. 



Tests for Wood in Paper. Wood is coming into extensive use 

 in the manufacture of paper, and a test for its presence may be 



