SCIENCE AND INDUSTRY. 
dry wood. When the converters are filled, they are closed, and diluted 
sulphuric acid added. They are subjected to steam pressure of 140 Ibs. 
The conversion takes place very rapidly, the filling and emptying and 
treatment of each converter charge taking only forty-five minutes. The 
condensed steam and acid liquor is drawn off and taken to neutralizing 
vats, while the treated wood is conveyed to diffusers, of which there are 
several, and subjected to treatment by water, by which most of the sugar | 
is extracted. Liquor is neutralized with lime, and then mixed with a 
special culture of yeast, and fermented in the usual way. I learnt that 
there is a considerable quantity of sugar carried away in chips, which 
are subjected to a rinsing wash, after they come from the converter, to 
free them, as fay as possible, from the acid liquid, then passed through 
a continuous press, which extracts most of the moisture from them, and 
then dumped in heaps. After’ being exposed to the atmosphere for a 
short time, they are dry enough to burn under the boilers in the usual 
way. 
In this particular mill the wood waste is charged at a very low price. 
I think it improbable that wood could be specially cut and treated in 
this way for alcohol to compete with alcohol from other sources. 
Next in importance to the cheap production of alcohol comes the 
question of its denaturation, or rendering it unfit for human consump- 
tion. The denaturant must be cheap, or it will add too much to the cost; 
nauseous, so that it will deter even the hard drinker from relishing it; 
and of such a nature that it cannot be separated by simple distillation, or 
any other operation which can be carried out without special skill and 
knowledge. The denaturant now most relied upon is methyl alcohol, 
or wood spirit, obtained by the destructive distillation of wood. Other 
substances are added. The wood spirit is in every way suitable, but it 
has the serious drawback of being scarce and dear, and is badly wanted 
for the production of other chemicals. Substitutes have been proposed, 
but they appear to be inacceptable to those who are responsible for the 
' protection of the revenue, so large a proportion of which is derived from 
potable aleohol. There is reason for caution in this matter, as the duty 
payable on potable alcohol is nearly 70s. per gallon, and power-aleohol 
would have to be sold at about 2s. 6d. per gallon. 
li is certain that there would be great danger of the revenue suffering 
if power-alcohol could be readily obtained, unless it were denatured in 
such a way that it would be practically impossible to produce a palatable 
beverage from it. As a preparatory step for the era of alcohol fuel, the 
Government should offer a handsome reward for the discovery of a suit- 
able cheap denaturant. 
From the foregoing it will be seen that there is little prospect of 
alcohol being produced at a price which will compete with petrol, even 
at the present high price of the latter, unless the Government is pre- 
pared, as a matter of public policy, to offer a bonus for its production. 
Any. such bonus would have to continue indefinitely, unless a fall in 
value of cereals;=umaccompanied by a corresponding decrease in the 
value of petrol; should take place. 
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