444 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



The rocs are there converted into a preparation largely used by 

 Germans called "caviar," the original of which is made on the 

 banks of the Volga, from a Russian species of the same fish. 

 Except that the globules of the Russian article are larger, thei^ 

 is very little difference between the genuine ariicle and the imita- 

 tion that comes from the Delaware and the Hudson. The pro- 

 duction of the stream first named, from some reason not to be 

 ascertained, is very materially the best. Thousands of sturgeon 

 roes have been thrown into the Delaware. They are now worth, 

 on the banks of the stream, a dollar and a half each. When 

 prepared in oil, converted into caviar, and sealed in tin cans, they 

 bring from sixty to eighty cents a pound. 



The Industrial Application of Oxygen. 



When illumiuating gas was first introduced it was compressed 

 iu strong vessels, just as soda water is at the present day, and 

 delivered to customers in their dwellings. Very fev/ persons had 

 the temerity to supi)ose that it v/ould ever be conducted through 

 the city in large mains, and be passed into every house through 

 connecting pipes. 



We now hear of the organization of companies in France for 

 euppljnng oxygen gas in portable receivers, the gas to be used for 

 purposes of light and heat. Vie may, some day, have oxygen 

 pipes carried along by the side of the illuminating gas, ready for 

 the various applications to which it is adapted. 



The only obstacle hitherto has been the expense. There are 

 many substances which yield oxj-gen in abundance, but they are 

 all too dear. M. Archereau has proposed the reaction of silica 

 upon the sulphate of lime as a source of oxygen. When these 

 substances are heated to a proper temperature, silicate of lime 

 and two gases — sulphurous acid and oxygen — result. The former 

 is used for the manufacture of sulphuric acid, and the latter it is 

 proposed to compress into cylinders and sell by the cubic foot. 

 The materials here used are very cheap, and the heat required to 

 fuse them will be obtained from a mixture of common gas and 

 oxygen. The silicate of lime could be used in the manufacture 

 of glass. 



The company which has been oi-ganized in Paris to make a trial 

 of this process, asserts that it can furnish oxygon at the rate of 

 two cents per cubic foot; whereas by the old methods, where the 

 gas has been employed iu the Drummond light, the oxygen has 



