SCIENCE AND INDUSTRY. 
Helium.* 
No element has had a more romantic history than helium, and few 
are of greater interest to men of science at the present time. Its 
extreme lightness, its absolute inertness, its close approximation to an 
ideal or perfect gas, and its: intimate connexion with the phenomena of 
radio-activity are among its most interesting properties, whilst its use 
for inflating airships and its possible application to a variety of other 
utilitarian purposes appeal especially to the student of chemical 
technology. 
The gases from some springs in France have been shown to contain 
as much as 5 per cent. of helium; natural gases in the Western States 
of America contain from 1 to 2 per cent., but within the British Empire 
no natural gases have been found to contain as much as 0.5 per cent. 
When, during the late war, it became apparent that the use of helium 
would have important advantages over that of hydrogen for filling air- 
ships, the Board of Invention and Research of the British Admiralty, 
acting on proposals advanced by Sir R. Threlfall, asked Professor 
McLennan to undertake a survey of the sources of helium within the 
Empire, and to devise ways and means of isolating it in quantity and 
in a relatively pure state. Natural gases from Ontario and Alberta, 
Canada, were found to be richest in helium (0.34 per cent: and 0.33 per 
cent. respectively), and it was estimated that these sources could supply 
from 10,000,000 to 12,000,000 cubic feet of helium per annum. Gases 
from New Brunswick were found to contain 0.064 per cent., and the 
richest natural gases in New Zealand not more than 0.077 per cent. A 
natural gas from Pisa, Italy, contained no helium; the gas at Heath- 
field, Sussex, 0.21 per cent.; that from the King’s Spring, Bath, 0.16 per 
cent.; and the natural gases at Pitt Meadows, Fraser River Valley, and 
Pender Island, on the Gulf of Georgia, British Columbia, were ascer- 
tained to possess a nitrogen content of over 99 per cent. : 
_ In 1917, a small experimental station was set up at Hamilton, 
Ontario, where it was found that the helium present in the crude 
natural gas, to the extent of 0.33 per cent., could be satisfactorily 
‘isolated on a commercial scale; and the second station was established — 
to operate on the natural gas at Calgary, Alberta. Three methods 
of isolating the helium content were investigated, viz., (a) by utilizing 
the cold obtainable from the natural gas itself for liquefying all the 
contained gases except the helium; (b) by using external refrigeration 
only, by means of ammonia, liquid air, &c.; and (c) by combining 
methods (a) and (b). Although method (c) had been successfully used 
in the Texas field by the United States authorities, it was not adopted, 
as it did not appear to be economical. Method (a) was selected, and 
by suitably modifying the Claude oxygen-producing column it was 
found that helium of 87-90 per cent. purity could be regularly and con- 
tinuously produced. Ultimately, an auxiliary apparatus was added, 
whereby the purity of the gas was raised to 99 per cent. or higher. 
a et Le pe, Pe 
sty vbstracted from a lecture delivered before the Chemical Society, by Prof. J. C. McLennan, on 
17th June, 1920, and published in the Journal! of the Society of Chemical Industry. 
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