The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1866-11-10
FORnreN soiENrrF1C ITEMS.
oPrIOAL ExpERIMrNrs.

,NuNl 10 the eject tnat the sun might be con-
Hmplated with impunity through lens covered
with silver leaf the latter being just tran sparent
enough TO allow of the suns disc being seen
very clearly, though 'shorn of its beamsS Last
week the Academy received a communication
from M Melsens, in which he described a very
useful application of NJ. FouCault's discovery,
lie states that about the beginning OF last july
ne received an injury nom the bursting
OF balloon containing q solution of iodine
and liquid sulphurous acid whereby both
bus eyes were attacked with violent iniamma.
nOn, which ne got the better OF by bold treat
ment. Nevertheless, the cure was NOT 40 com
plete but that great Weakness of the ewes re-
NAMED (photophooisl, 50 that light was painful
TO him. He then had recourse to tbe sort of
spectacles used by engine drivers ON railways
These spectacles are provided with black glasses
ana as these we're still too transparent, N. Mel
sens put green ones over them. In this way thCy
answered toerably well; but the author uIt-
mately used pTeservers with pale blue glasses
when ne covered, not chemically but mecha-
nlcally, with either gold or silver leaf and this
he found to answer best of all the light so trans
Inltted being exceedingly pleasant especially i'm
the ease OF gold leaf The latter, when yellow.
lets green light pass; when green that is allowed
with silver the eye receives blue light NJ Mel
sens therefore thinks that persons laboring under
lhe Inconvenience OF weak eyes will derive
Ereat rehef rom spectacles SO prepared and we
trust the present article may catch the eve of
persons SO circumstancedp
NEW PLANET
At the last meeting of the French Academy of
Sclences, an announcement of the discovery of
new telescope planet was received from Nj.
Luther. 1t has been named Antoine and ts the
nnetieth OF the series. The positions observed
at Blk on the lst instant were:-Mean time llh.
~ min. 24'S sec; Il. A., Oh. min. 1906 sec.;
south declln., deg. II min. 1875 sec. Durnal
motion in h. A. retroerade, A Sec; in south
deciin., ~ min. The same planet has also been
observed at Berlin.
STELLAR LIGHT.
The Academy has also received letter from
Father Seccni OF Rome on the spectrum ANALYSIS
OF stellar light. In examining a large number
"i staIs, he says he was struck with The uni
tormity OF their luminous constitution. He dis
ungulsheS three diaereut types: one commonly
called the type of white stars like Sirius etc:
another comprises the stars whose light produces
red or orange-colored bands in the spectrum;
and TO third belong the stars PRODUCE NO yery
narrow bands In the first type he has foun an
exception: Gamma CassiopGe, whicn, instead of
having dark band az F-a point OF the spectrum
well known TO those who possess a map of it. ,
has a luminous one instead. 0 the stars pertain.
ng TO the second type, Alpha Hercus is the /
most remarkable. 1t is OF the third magnitude, !
and yields spectrum the hands of which !
appear in relief like the pillars of a long colon |
made The stars oi the third type might be |
appropriately called solar, their spectrum bear
lag the strongest resemblance to that of the |
sun. Another remarkable circumstance is this |
that each ofthese types appears to be dominant
IN some one or other of the celestial regions.
q III readers may remember our giving an ac-
co1nt of II. GIimaud de CauX's papers in winch
he maintains that cholersy is scontagiousyand
0npht to Oe prevented by means Of strict quar-
buLlnG we ALSO HdNc hDSlTaCtS OF the replies |
Wb ch his papers elected, and in which every
one of his arguments was demolished ; besides
which, we suppose our readers are themselves
personally aware as we are, of tacs in direct |
opposition to NJ Grmaud's views. NeVerthe-
less he has thought proper TO address another
paper 70 the Academy in which, after attempt
ing to cover hrs retreat by means Of a quibble
OF dates, he expresses himself as follows: ''If
in REGARD 10 cholera, science has advanced a
step through the now nnlmpeachable demon
stration CT the transmssiOiity of that terrible
m If iG n fp mo - In tho
mer, would be retreshngly cool.
STATISTICS OF PHOTOGRAPHY.
The rapid growth of new and special indus /
tries, says the British Quarterly ReUteo, Is a fact
so characteristic OF the present day, that the ,
statistics of photography can scarcely be re-
garded as wonderful. viewed merely as a ques
ton of economies. Nevertheless some of the !
facts are sufficiently startling. Twenty years
ago one person claimed the sole right to prac-
/ tise photography professionally in England. |
According to the census of 1861 the number of
persons who entered their names as pho
tOgraphers was 1884. There is reason,
however TO believe that these figures fall
| short of the real number; since then il is /
probable the number has been doubled |
or tIe6led, and that, including those
four or five times that number. But these
figures fall short of the number interested in
photography as amateurs. We are informed (
that eight years ago, in establishing periodical /
which has since become the leading photo |
graphic journal, a large publishing firm sent |
N out twenty-five thousand clrCuarS-nOt SCWn |
\ broadcast, but specially addressed 10 persons |
/ known to be interested in the new art science. |
] The number of professional photographers in |
the United States is SAID to be over fifteen thou |
sand and q prOpOrtiOnate number may with pro- |
pTiety be estimated as spread over continental |
J Europe and other parts OF the civilized globe.
But more curious estimate OF the ramidca-
tlons o. this industry may be formed by glance
/ at the consumption of some OF the materials en- |
/ ployed. single firm in London consumes, on
an average, the whites of two thousand eggs
daily IN the manufacture of albumenized paper |
! Tor Photographic printing, amounting to six !
hundred thousand annually. As it may be
fairly assumed that this is bat a tenth OF the !
total amount consumed in this country, we OBJ !
tain an average OF 81 millions OF inchoate fowls
sacrificed annually in this new worship of the |
sun in the United KINGDOM alone. When to |
this is added the far larger consumption OF
Europe and America, which we do not attempt
to put in figures, the imagination is startled 6y
the enormous total inevitably presented for its
realization.
In the absence of exact data we hesitate to
estimate the consumption of the precious
metals, the mountains Of silver and monuments
of gold, which follow ms matters OF necessity.
A calculation based on facts enables us 10 state,
however, that Tor every twenty thousand eggs
employedl nearly one hundIcdweight OF nitrate
OF silver is consumed. We arrive thus at an
estimate lof three hundredWeightl of nitrate of
silver annually used in this country alone in the
production OF photographs. To descend to indi'
yidual facts more easily grasDed, VIC learn that
the consumption of materials In the photo
graphs OF the International Exhibition OF 1862
produced by MIR. England for the London Stere-
oscOpic Company amounted to tWenty-four
ounces of nitrate OF silver, nearly hfty-four
ounces OF terchloride of gold, two hundred 0aI
Ions of albumen, amounting to the whites of
thirty-twO thousand eggs and seventy reams of
paper: the issue OF pictures approaching Il,