194 ANNUAL OF SCIENTIFIC DISCOVERT. 



bonic acid passed. After a few hours, the silvery aspect of the 

 metal changed to a red mass, and ultimately became nearly black. 

 Toward the end the heat should be moderated to avoid reduction 

 to carbon, and the whole slowly cooled. Left in the air for the 

 sodium to oxidize and then exhausted with water, it furnished a 

 solution containing oxalate of sodium. From 10 parts of sodium 

 1 part of calcic oxalate was obtained. Potassium amalgam con- 

 taining 2 per cent, of the alkali metal acts in the same way. 



GLASS FOR CHEMICAL PURPOSES. 



Prof. J. S. Stas, wishing to ascertain what should be the compo- 

 sition of glass at the same time unaffected by acids and sufficiently 

 fusible to be easily manipulated, instituted some experiments, with 

 the result that a glass having for bases sodium and calcium, if it 

 contains a sufficient excess of silica, resists acids almost as well 

 as refractory Bohemian glass, having for bases potassium and 

 calcium. It being known that a mixture of equal molecular 

 weights of the carbonates of sodium and potassium is much more 

 fusible than the most fusible of either carbonate by itself, he en- 

 deavored to replace, in the composition of refractory glass unat- 

 tacked by acids, a portion of the potassium by an equivalent 

 quantity of sodium. A very refractory glass being obtained by 

 about, 



Silica, 75.00 



Oxide of Potassium, 15.00 



Oxide of Calcium, , 10.00 



100.00 



he replaced. in such a glass half of the potassium by its equivalent 

 of sodium, thus : — 



Silica, 77.00 



Oxide of Potassium, 7.70 



Oxide of Sodium, 5.00 



Oxide of Calcium, 10.30 



100.00 



In this glass the bases are in the proportion of 1 atom of cal- 

 cium (Ca'' = 40) to 1 atom of potassium and 1 atom of so- 

 dium. ^ The glass made according to this formula had a yellowish 

 reflection, was excessively hard, but little elastic, and as free from 

 hydrometric properties as the best refractory glass of Bohemia. 

 — Chemical News, Jan., l^Q^. 



OZONE AND ANTOZONE. 



An experiment of Schonbein, illustrating the simultaneous 

 formation of ozone and antozone, is as follows: Into a flask of 

 600 c. c. capacity, and 3 or -i centimetres in diameter across the 



