APPENDIX A XXXVII 
This was produced by the action of electricity on the air in presence of 
lime and carbon. This compound, which can, it is said, be cheaply made, 
contains about 20 per cent of nitrogen, and field experiments on crops in 
Europe during the past three years have shown satisfactory results from 
its use. 
Priestly was the first to discover that when a mixture of nitrogen 
and oxygen is subjected to the action of electricity a combination is 
effected and a mixture of nitric and nitrous acids formed. In 1898. 
Sir William Crooks, in his annual address before the British Association, 
pointed out the great possibilities in atmospheric air as a source of 
nitrates for fertilizing the soil and showed that it was possible by the use 
of a powerful current of electricity to combine the nitrogen existing in 
the air with the ozygen also found in the air and thus to make nitric 
acid. In this way the means could be found to increase the productivity 
of the grain growing areas in the world, without which he maintained 
there was danger of a shortage in the supply of wheat in the future. Ie 
ventured to predict that electrical energy produced by water-falls would 
at no distant time, be utilised for the production of nitrogenous com- 
pounds suitable for plant food. 
Attempts to realize this prediction have recently been made in 
several countries. An American company was formed with this object, 
which had at its disposal, at Niagara Falls, several thousand horse power. 
After spending about a million dollars, considerable quantities of nitric 
acid were made but it was found that the cost of manufacture was too 
great to permit of the company competing successfully with the present 
sources of supply. Hence the project has been abandoned. 
A similar misfortune overtook a company which organised a plant 
with a similar object at Freiburg in Switzerland. 
Quite recently, however, information has been received to the effect 
that Norway has solved the problem. A large plant has been established 
by a syndicate having at its disposal from several large water-falls, about 
400,000 horse power. The works have been established at Notodden, 
near the falls of the Tenelf, which furnishes the necessary electrical 
energy. At this factory more than 33,000 lb. of pure nitric acid is 
made per day, directly from the air. From 10,000 to 20,000 horse power 
is said to be necessary to carry this work on successfully. The nitric 
acid is saturated with lime and the resulting calcium nitrate is used as 
a fertiliser. The particulars of the process are not yet fully known, 
but it is said that nitric acid can only be made at present at a price to 
stand the competition of the nitrates from Chili, where the power from 
the water-fall can be had for about three dollars per horse power per 
year. 
