Evening star. [volume] (Washington, D.C.) 1854-1972, 1891-07-11

Written for The Evening Star
WHAT THE SUNS RAYS CAN DO.
Some Day They May BE Harnessed for Work.
ing the Worlds Machinery.
HOW THEY BUILD PLANTS AND MAKE HUMAN BE-
INGs-wrLL THE ORB OF DAY BURN OUT AND
THE EARTH BECOME DEAD PLASET?-wHAr
BURNING GLASSES CAN Do
I IS VERY CURIOUS THING TO CON-
u slider that every human being has literally
been made by sum- rays. Whatever one eats. the
material of which goes to compose the body is
made to grow by the light and heat Of that
heavenly orb. Upon Its effulgence the plants
depend for their development, and upon things
vegetable all animals must rely for food. Thus
IL may be said that every man or woman rep
resents . certain quantity of stored solar
energy.
Inc force Of gravitation constantly sum-
mons attention, because the whole scheme Of
existence depends upon it, but, while the
power that pulls things down is SO evident,
now many people ever consider the mysterious
potency OF the sunbeams to lift things up? 1t
Is not the soil that upraises the plant. Phebus,
as the ancients called him, builds all the trees
OF the forests. Not only does he set one parti-
Gle OF matter on top of another in the process
OF construction, but in each tree
HE LOCKS UP A STORE OF ENERGY
thousands of times greater than that which was
expended in merely erecting the trunk. This
may be seen when the energy is unlocked by
burning the tree under the boiler of an engine
which will produce power enough to raise thou
sands of logs equally big. The monarch of
| N1, I'll Al
soil, though still keeping imprisoned within
1t fol- millions of years the energy
which ages afterward may be liberated
to run a printing press or other machine.
ms newspaper itself Is printed by sunbeams
which fell upon the earth ever so many
turtles before man was first born. The paper
on which these words are marked was made
from material grown by the sun. With little
trouble taken for the purpose of calculation
the amount OF solar radiation expended for
turning out the sixteen pages of today's STAR
could be stated with approximate accuracy.
HOW LONG WILL TIE COMBUSTION LAST.
Prof. S. P, Langley. secretary If the Smith
sonian Institution. calls attention to the fact
that the human race is main tanning existence
by keeping itself warm at this great fire of the
sun, which called the genus homo into being.
When it goes out mankind Will vanish also
The question is therefore of the most absorb
ing interest how long the conbus-
ton has lasted, for what length Of
time it will continue TO endure and
OF what nature it is. Respecting its intensity
many comparisons might serve for she purpose
OF conveying vivid notion to the mind. For
example, suppose that all the ice and snow at
the arctic and antarctic poles could be swept
together and a tower made of the material
fifteen miles in diameter. Imagine that it could
be preserved untouched by melting
while the Accommodations of successive
winters were heaped upon 1t until it should be
200 miles high and stretching to the moon.
Then conceive that there should be concen-
trated upon it the suns entire heat for one
second In that brief time the whole would be
gore-nelted, boiled and dissipated in vapOr.
NOT ORDINARY BURNING.
How is this heat maintained? 1t is readily
proved that if the sun itself were one solid
block Of coal it would burn out altogether
within a few centuries. But it is known abb
solutely that during historic times there has
been no noticeable diminutiOn of the suns
heat for the olive and the vine grow Jus: as
the. did and where they did 5000 years
ago. Thus it Is evident that the process con
cerned is not one Of ordinary burning. Only
one theory would account for the phenomenon,
and that IL unique stionabl, the true one
namely, that the suns own slow contraction
develops the heat it gives out. OF course there
must be an ultimate limit to the shrinking Of
that wondrous sphere of flaming gas. and
science looking into the future declares
that the heat supply is enough to last
four or five million of years longer
before it sensibly fails. Within ten
millions of years it will have ceased to give out
any warmth worth mentioning. but before that
period arrives man will have discontinued his
interest in the subject. inasmuch he will
long previously have passed off the face of the
earth. which will then be reduced to the CON
dition of dead planet like the moon. OBJ
viously. it is possible that some wandering star
may fail into the sun and in this way restore
the wasted energy of ages by the collision, bat
such an event seems hardly likely.
VERY STRIKING ILLUSTRATION
of the power of the suns rays is afforded
by a simple lens used as a burning glass.
No very great burning lens has been con-
structed for long time. During the last CEN
fury an enormous maze in France.
all the heat falling upon it being
concentrated upon smaller and
the smaller one concentrating it in
turn. until at the very focus it is said
that iron, gold and other metals ran like melted
butter. In England the biggest burning glass
on record was made about the same time for
the British government, which designed it a
present for the Emperor of China. 1t was
three feet in diameter and beneath it even the
diamond was reduced to vapOr. The emperor
when he got his lens, was much alarmed lest
possibly it was sent by the English for
the purpose Of injuring him. BY way OF test
smith was ordered to strike it with his ham
mer. but the hammer rebounded from the
solid glass and this was taken to be conclusive
evidence of magic in the thing, which was i'm
mediately buried and probably is still repeating
under the soil OF the celestial kingdom.
TO RUN MACHINERY.
Many attempts have been made to utilize the
suns rays for running machinery. The idea
ought to be in some way practicable. inasmuch
as every square yard of earth receives enough
energy in the shape of sunbeams to represent
one horse power. Even on such a
small Manhattan Island the
noontide heat is enough, could it all
be utilized, to drive all the steam engines in
the world. Sun machines have alredy been
made to go, though not successfully as yet from
the economical point of view. However. the
day is not unlikely to arrive before long when
the thing will be done and the orb of day fairly
harnessed for working all the engines ca the