SCIENCE AND INDUSTRY. 
turn the engine several times. As the throttle is opened, a supply of 
alcohol is taken up from the carburetier, and the engine continues to 
run. The raison d’étre appears to be that when the engine is turned 
with the throttle closed, a partial vacuum is formed which induces rapid 
evaporation of the alcohol, and in a few turns the formation of a mixture 
sufficiently rich to ignite. It remains to be seen whether this method of 
starting will be practicable with heavy engines, but it has succeeded with 
most of the numerous makes which have been experimented with. 
Another method of overcoming the starting difficulty is to convert a 
portion of the alcohol into ethylic ether. An alcohol-ether mixture con- 
taining about 30 per cent. of ether gives easier starting in cold weather 
than the ordinary grades of petrol, and has the advantage of giving a 
more concentrated fuel than alcohol, which contains only 10789 B.T.Us 
per pound, compared with petrol and ether, which contain 19162 and 
15476 units respectively. 
The calorific value of the respective fuel shown by these figures does 
not necessarily indicate that nearly two units of alcohol are required to 
do the same work as one unit of petrol, for alcohol will give greater 
engine efficiency; indeed, it has been claimed by experimenters that 
alcohol can be made to do about the same amount of work, weight for 
weight, as petrol. The experiments made at the Melbourne University 
for the committee have not altogether substantiated this claim. The 
increased efficiency of alcohol over petrol would also probably be obtained 
with the aleohol-ether mixture. The cost of converting the required’ 
proportion of the alcohol into ether is not very serious. I investigated 
the matter both in England and the United States of America, and 
reported to the Prime Minister in February, 1918, that where ether is 
made in large quantities, as was the case in England for the manufacture 
of explosives during the war, the cost of manufacture was slightly over 
£2 per ton, depreciation of plant and all overhead charges included. 
A- company was formed for carrying on commercially the manufac- 
ture of alcohol-ether motor fuel in South Africa, but I have not yet 
learned what results are being obtained either ‘in the manufacture or use 
thereof, but definite information should now be available. 
The foregoing will show that there are no technical difficulties in the 
way of using alcohol, but, unfortunately, when it comes to the com- 
mercial aspect the outlook is not encouraging. 
In the report to the Prime Minister, previously referred to, I made 
use of the following words:—“ While alcohol is produced synthetically 
from acetylene—and some from refuse liquors arising from the manu- 
facture of sulphite wood pulp, and still more from saw-mill waste—it is 
safe to say that at least 99 per cent. of the world’s alcohol supply still 
comes from various farm, plantation, and fruit crops. Upon the price, 
therefore, at which the farmer can give us those crops, it at present 
depends whether it will be practicable to use aleohol instead of petrol 
as an engine fuel.” The position is still the same, although in Norway 
and some other countries in which sulphite wood pulp is largely pro- 
duced, the manufacture of alcohol from the refuse liquors has assumed 
large proportions. Some progress has also been made in its synthetic 
production, the new source being ethylene, extracted from coal gas. The 
process is considered very promising, though details as to cost are not 
yet available. 
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