At a popular fête in the Tuileries Gardens I was struck with an
experiment which seems deserving of the immediate attention of the
English public and military authorities.
Among the attractions of the fête was an apparatus for the concentration
and utilization of solar heat, and, though the sun was not very
brilliant, I saw this apparatus set in motion a printing machine which
printed several thousand copies of a specimen newspaper entitled the
_Soleil Journal_.
The sun's rays are concentrated in a reflector, which moves at the
same rate as the sun and heats a vertical boiler, setting the motive
steam-engine at work. As may be supposed, the only object was to
demonstrate the possibility of utilizing the concentrated heat of the
solar rays; but I closely examined it, because the apparatus seems
capable of great utility in existing circumstances. Here in France,
indeed, there is a radical drawback--the sun is often overclouded.
Thousands of years ago the idea of utilizing the solar rays must have
suggested itself, and there are still savage tribes who know no other
mode of combustion; but the scientific application has hitherto been
lacking. This void this apparatus will fill up. About fifteen years ago
Professor Mouchon, of Tours, began constructing such an apparatus, and
his experiments have been continued by M. Pifre, who has devoted much
labor and expense to realizing M. Mouchou's idea. A company has now come
to his aid, and has constructed a number of apparatus of different sizes
at a factory which might speedily turn out a large number of them. It is
evident that in a country of uninterrupted sunshine the boiler might be
heated in thirty or forty minutes. A portable apparatus could boil two
and one-half quarts an hour, or, say, four gallons a day, thus supplying
by distillation or ebullition six or eight men. The apparatus can be
easily carried on a man's back, and on condition of water, even of the
worst quality, being obtainable, good drinking and cooking water is
insured. M. De Rougaumond, a young scientific writer, has just published
an interesting volume on the invention. I was able yesterday to verify
his statements, for I saw cider made, a pump set in motion, and coffee
made--in short, the calorific action of the sun superseding that of
fuel. The apparatus, no doubt, has not yet reached perfection, but as it
is it would enable the soldier in India or Egypt to procure in the field
good water and to cook his food rapidly. The invention is of especial
importance to England just now, but even when the Egyptian question is
settled the Indian troops might find it of inestimable value.
Red tape should for once be disregarded, and a competent commission
forthwith sent to 30 Rue d'Assas, with instructions to report
immediately, for every minute saved may avoid suffering for Englishmen
fighting abroad for their country. I may, of course, be mistaken, but
a commission would decide, and if the apparatus is good the slightest
delay in its adoption would be deplorable.--_Paris Correspondence London
Times_.
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