2^G Prof. Thompsoti on Electric Production of Nitrates. [Feb. *2, 



In the furnaces, as used in Norway, the disc of flame was four or five 

 feet in diameter, and was enclosed in a metal envelope lined with 

 firebrick. Through this furnace air was blown, and emerged charged 

 with nitric oxide fumes. These fumes were collected, allowed time 

 further to oxidize, then absorbed in water-towers or in quicklime — 

 nitric acid and nitrate of lime being the products. The research 

 station near Arendal was described ; also the factory at Notodden, 

 in the Hitterdal, where electric powder to the extent of 1500 kilo- 

 watts was already taken from the Tinnfoss waterfall for the produc- 

 tion of nitrate of lime. This product in several forms, including a 

 basic nitrate, was known as Norwegian saltpetre. Experiment had 

 shown that it was equally good as a fertilizer with Chili saltpetre ; and 

 the hme in it w^as of special advantage for certain soils. The yield of 

 product in these furnaces was most satisfactory, and the factory at 

 Notodden — which had been in commercial operation since the spring 

 of 1905 — was about to be enlarged ; the neighbouring Avaterfall 

 of Svaelgfos being now in course of utilization would furnish 

 28,000 horse-power. The Norwegian company had further projects 

 in hand for the utilization of three other waterfalls, including the 

 Rjukanfos, the most considerable fall in Telemarken, which would 

 yield over 200,000 horse-power. According to the statement of 

 Professor Otto Witt, the yield of the Birkeland-Eyde furnaces was 

 over 500 kilogrammes of nitric acid per year for every kilowatt of 

 powder. The conditions in Norway were exceptionally good for the 

 furnishing of power at exceedingly low rates. Hence the new product 

 could compete with Chili saltpetre on the market, and would become 

 every year more valuable as the demand for nitrates increased, and 

 the natural supplies became exhausted. 



[S. P. T.] 



