The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1869-08-04

| blished a new and exact meridian line TO be
called after that city, one hundred and fifty feet
due west of the new State House dome. A
| square shaft of marble, sunk seven feet in the
| ground, marks the spot. The tents for observa-
ton are there erected, and all the necessary ap-
paratus is at hand
The Kentucky Corps.
Professor Joseph Winlock, of Kentucky has
charge of the observations to be made in that
State by the Observatory of the Harvard Col
lege and the United States Coast Survey. The
two important points i'm Kentucky are Fall
mouth in Pendleton county, and Oakland,
south of Cave City, at the farm of j. b. Wilder,
Esq, of this city. Mr. Wilder has kindly
placed his house at the disposal of the astro-
nomical corps assigned to Oakland. There are
many intermediate points between Falmouth
and Oakland at which important observations
may be made, especially at telegraph stations
where the Morse paper flet is used, and at
these points Mr.. Boyle, of the Union Telegraph
Lines, is directing his attention. The other
telegraph lines in the State will be called upon,
and will undoubtedly lend their aid in this i'm
portant work Professor Winlock has with him
a very able astronomical corps, who will be
distributed to the important points for obser-
vations. He has also an ample supply of in
Struments of unsurpassed excellence for per-
these are spectroscopic apparatus with astro-
nomical attachments, with which it is expected
very valuable contributions to science will be
made.
Meteorological Observations.
Commodore B. f. Sands, Superintendent
United States Observatory, has issued Il circular
to meteorological observers along the line of
totality in which he says:-
As,the United States Observatory is to have
all its available force in the field, expecting to
contribute its full share of labor on this occasion
1t is desirable that during the eclipse of the sun
meteorological observations should be made
within the belt of totality, with a barometer, a
dry-bulD thermometer, wet-bulb thermometer
a solar thermometer, with blackened bulb in
closed, if possible, in glass cylinder from which
air has been exhausted, and an actionometer.
The barometer should be suspended in the
shade, and, If provided with a thermometer, the
temperature should be determined at each read
ing. The dry and wet-bulb thermometers should
be suspended in the shade in such manner as
to prevent, rs far as possible, the abnormal in
huence OF radiation from surrounding bodies,
and at the same time secure a free circulation of
the air.
The solar thermometer should be placed in
slender wooden crutches about six inches above
the green grass of a field or lawn, and in To-
cality where the direct solar rays shall reach it
from sunrise to sunset
Observations with the actOnometer should be
made in the open air, and the bulb should, as far
aSpracticable, be protected from the influence
ofDair currents.
If possible, observations should be made at
each hour of the day and night of the 9th, 7th,
and Sth of August, beginning at midnight of
the 5th.
If observations cannot be made during the
night, great care should be taken to make them
carefully at each hour of the day.
A careful statement of the character of the
weather should be made at each observation.
On the 7th of August observations with the
aptiOnOmntpr ot A md ko
made at intervals of thirty minutes until the first
contact OF the limbs of the sun and moon, when
they should be continued at intervals of ten
minutes uutil the last contact, or until sunset
One observation should be made, if practicable,
during totality.
The barometer should be read at intervals of
twenty minutes while any portion of the sun is
eclipsed and once during totality.
The thermometers should be observed at in
tervals of ten minutes during the eclipse and
once during tOtality.
The time of the beginning of the total obscu-
ration should be carefully noted by the clock or
watch by which the meteorological observations
are timed.
All persons who may make such observations
as described will confer great favor if they will
forward their observations together with the
errors OF their instruments, if known, to the
Superintendent of the United States Naval OBJ
servatory, Wash ington d. G..
Scientific Problems.
The number and equipment of these scientific
eXpeditionary corps testify more strongly than
mere words could do to the intense interest felt
among educated men to accumulate further data
Tor solving the problems of the constitutions of
the sun and moon, the composition of solar
light, etc. The theories thus far broached are
all under trial.
The explanation usually given of the white
corona is that it betokens a transparent, nom
luminous atmosphere, extending beyond the
| photOsphere or luminous atmosphere analo0Ous
| to our own atmosphere The white light of the
corona is accounted for by the reflection of that
OF the photosphere, very much as our own even
| ing and morning twilight is produced by the re-
hection OF the solar rays in our atmosphere.
| The irregular red masses seen projected
into the white corona may prove
| to be immense volumes of thin cloudy
smoke, or solid yaporous particles preciptated
from the hot gaseous atmosphere which forms
the corona. But there are various objections to
these views. Nothing is as yet definitely set
tied; further observations and discussions are
needed to Hlro1o light on the suns physical con-
sutution. One observer with the spectroscope
pronounces the red or rose-colored projections
to be red-hot hydrogen The question of an
other planet or planets within the orbit of Mer
curry, as suggested by lie Verrier, to account for
certain extraordinary perturbations of this
planet, remains also to be settled. The total
eclipse OF the sun affords good opportunity to
search for the new planet or planets.
Solar Photographs.
The method OF taking photographs of the sun
was illustrated during the late experiments of
the Philadelphia corps before starting westward.
and is worthy a description.
The telescope is directed towards the sun and
IT'S clock work Is set in motion so that il may,