The daily dispatch. [volume] (Richmond [Va.]) 1850-1884, 1860-07-21
Rittmonn Qispatth.
SATURDAY MoRNINa. JULY "a. lsso.
How the Eclipse was Taken by the As.
tronomprx

AAoW sHS 6ShP>S W"@ A""'h ~s s"e ms
trsnomers.
The morning sun of Wednesday rose veiled
In haze. which it threw of as 1t assembled the
heavens. Then appeared, overspreading the
xky. drifts of ganzy clouds. which the gather
ing heat soon dissipated, 30 that when the
eelipse began, the atmosphere was beautifully
clear. The Tribune gives description of
how IL was taken at the Rutherford Ubserva-
tory
As the time given by the astronomical Ia
bIes approached, Mr.. Rutherford took position
at the great equatorial, mounted on q plat
form, TO watch for the instant of appulse OF
the limb Of the moon upon the suns edge
Nearly the whole of the suns light was cut
of by means of a screen of pas eboard, having
An aperture OF but two inches. placed upon
the object glass and the in .ensty of the light
that sill streamed down throp gh the tube was
tempered to the eye by dark-colored circles of
glass
As the critical moment drew near, every
tongue was silent, ana nothing was audible
but the slow, heavy tick. tick of the chro-
nometer clock. beating seconds, and the quick
er te-rick-ah te-riek-ah of the beautiful
clock. attached to the great equatorial,
and which keeps the object under examina-
ton steadily in the field of view. There were
three chronometers in use. Now every man
is at his post, and ALA Atillps. An iadiscreet
question by a visitor breaks the silence but
me person addressed gives no heed. All watch
the lapse of the seconds with bated breath
Twenty ~ "haIf!' some ~ "halfi" "two.
half" connts each time-keeper, with eve
riyeted on the chronometer before him: and
round and round goes the nervous little se-
cond hand, beating ont time with quick
firm jerk. Three :" "half - four I" half n'
"fve!" "balfr'
"Time :" shouted the observer
l have it 255 seconds, 56 minu tes, hours
sderal time at Greenwich by the chronometer
clock, aud the serrated limb of the moon has
entered the perfect edge of the suns disc. Mar
...l, a.
ma athematician, that figures do not lie! Not
merely Ole day or year in advance does the
astronomer announce his prediction of these
epochs, but for centuries to come he forewarns
the watchman OF the skies of the precise place
and instant of each in terest ting phenomenon
81 never saw sharper or clearer en trance ;"
observed Mr.. Rutherford, as he stepped down
on the floor and went out. There was a feel-
ing OF satisfaction apparent on every face
What a beautiful atmosphere" said the Pro-
fessor, with Zest "How clear and steady -
The thermometer is now onsulted-6S.5 Fab
renheit, it says. Then follows a comparison
of notes, and all are ready again for the next
event
Mr.. Rutherford enters, bringing q wooden
frame, perhaps ten inches square, dripping as
with water He mounts the stand and slides
the frame into camera box, which had been
adj just ted to the tube of the equatorial before
the eclipse began. The small aperture of per-
haps half an inch in diameter, in the neck of
the camera box, which admits the rays OF the
e.
This slide has an aperture in the middle of
II corresponding to the aperture in the box.
1t plays upon pivot, and q spring is fitted to
1t. A touch liberates the spring and the slide
flies across the aperture, giving passage to
the solar beams and cutting them off again in
stan taneously.
MIR. X. gives warning of readiness. and all
are again on the qua rtrs Ready - he cries
without particle of uns teady excitement
Fifty eight !" "Halfin mine ~ "Halftv
Sixty :" "Half!' "Onen "Halfr'
"Click"' The slide has sprung! The pic
ture is taken The sun and moon are photo
graphed, touching hands at their nu ptals
l.5 Sm., 3h., sideral time at Greenwich
There is manifest in terest in every face, but
agitation, no furry, and the calmest of all is
the chief operator himself.
Another look at the thermometer-695
| What beautiful group of spots y excaims
| the Professor, gazing through the "fnder'' of
| the great telescope. We must have the i'm
mersion of them Ready for time.
| All stand at their posts, and repeat the min
utes as the strong tick of the clock unds them
out in the stiffness. Seconds grow to mi ut tes
and minute succeeds to minute the uneven
| limb of the moon slowly moves, under the
steady gaze of the Professor, toward the in ter
esting object. "Time !" 22s 14in 3h "Ap-
pulse of largest CUTLER of group of spots,' the
Professor announces loudly. "Ready again ~
"Time.' 39s. Ism 3h. Contact with penum-
| bra of large spotr' Ready again ~ Thine W
| 39s Ism. 3h. Contact of nucleus of ditto"
The proprietor here re-enters with a second
puulOSEdpulC pldtt anu OTO6T proceeds as
| before-another and another. till ten pictures
| are taken.
| AS the eclipse wears toward its end Mr. r
| rests satisfied. The camera box is removed
| the beautiful eye-piece fitted on and u
| screen, with larger aperture than had been
| used in taking the photographs, fitted to the
object glass. After some few general obserya.
| tions through the glass, attent tion is once more
| summoned, and all stand ready again TO record
| the instant when "time" is called-the ins tan
| of emersion. n 4 Slowly the min
utes go. n Round and round once
twice. moves the small nervous finger of the
| seconds. X Slowly slowly X
The interest is great, the silence audible
"Time ~ 2725s. SIM. 4h., and the eclipse is
over!
There now remains to "reduce" the time
given by the chronometers to "mean time" for
The place of obseryation-if such technical
phrases may be allowed without explanation
and the record of the solar eclipse al this OBJ
servatory is complete.
The thermomeIric records made during the
progress of the eclipse exhibit the in teres ting
fact thatdnring the first half of the eclipse the
mercury rose ABOUT one degree; during the las t
half, four degrees, and during the nineteen
minutes succeeding, one degree.
WATER GAs.-Mr. Paine and others, who
have made so many promises of gas and light
from water, must "look to their IaureIs for
what they only talked about appears to have
been accomplished by Frenchmen. The city
OF Narbonne, in France, has been lighted by
genuine water 2as for nearly three years. The
SO called water gas of White Sanders and
others, is only mixture of hydrogen with ceaI
or resin gas, but the Narbonne gas is pure hy-
drogen.
The first process at Narbonne was 10 decom-
pose water by passing steam through highly
heated retort ontaining COAL The explana-
tion OF the decomposition is that the carbon
takes away the oxygen from the water, thus
setting the hydrogen free, the carbon and oxy-
gen com bine and become carbonic acid and car
bonic oxyd. The chief objectio to his process
Is, that the heat req uired to effect the decompo-
sition is so great that the retort is destroy
edi hydrogen produced in retorts, by the best
management, would probably cost more than
oil, coal, or resin gas. But lately at NarbOnne
they have entirely dispensed with retorts, and
decompose the steam by passing it directly into
the furnace
Tie furnace, of the cupola form, is charged
with coke, the fire urged by a blast and when
the whole is intensely heated the blast 10 shut
on the Hue closed, and steam at 80 lbs. is let in.
Ihe steam is decomposed and the gases pass
away to the purifier and gasometer. The sys-
TEN seems plausible, but req uires the practiced
test to fix its value
The gas generators erected at the above place
nave oeen In successful operati q about six
months, have cost nothing for repairs; and NJ
RACES, the inventor, thinks they will last an
Indefinite period. Each generator produces
ouvoo ieet OF gas In "a hours, at a cost for ma
teriais COKE, coal and lime) of about 20 cents
per l,OOO. The period of admission of steam
and generation OF gas is about 2U minutes of
the re-heating four or five minutes
The gas thus produced on burning gives lit
tie light but great heat. Light is secured by
adjusting over the burners coils of fine plati-
mum wire.-ScisR.ife Anerican
PHYSICIANS IN CHIHA.-In China there Is free
trade in physic-a good principle enough, but
which has not yet led to all the desirable re-
forms in that art. A dose of Chinese medicine
is quite curiosity. 1t about the size OF
half pound of moist sugar, and consists of