The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1869-08-12
THE ECLIPSE IN NEW YORK.

METEOROLOGICAL OBSERVATORY, CENTRAL,
PARK, New YORK, Aug 8, 1S69.-To the Com
mlssioners of the Central Park-Gentlemen
i have the honor to submit the following
report of the meteorological effects of the
eclipse of the sun which took place yester
day, Aug Z, 1869. Time of commencement
at New York, five hours and twelve minutes.
End, sunset. The observations herein re-
corded were made with the self-registering
instruments we have recently placed in the
observatory of the park. Those used on
ter; (2) barometer; (3) vane for
direction of the wind % instrument
for determining pressure of the wind:
90 instrument for determining its velocity
The two first are Photographic registers, the
other three are pencil machines. They were
all in satisfactory working order. l have not
thought it necessary to introduce herein the
indications of the wet-bulb thermometer, as
they do not bear upon the subject, though
we have a complete record of them, nor of the
blackened bulb thermometer exposed to the
sun, as the interruption of clouds rendered it
useless shadow or observation suddenly
fell upon the earth 1t covered several mil
lions of square miles of surface IL extended
from Eastern Russia across the North Pacific
Ocean, spread over the whole continent of
North America, and reached the North Allan
tic The zone of maximum darkness, about
40 miles in width-the path of the umbra-
divided our continent almost symmetrically
into a northeast and southwest portion,
giving, therefore, singular interest to
any meteorological observations that
might be made-an interest increased by the
fact that there will be no total eclipse again
here visible during the present century We
might, perhaps, expect that an observation
suddenly occurring over 50 vast an extent of
the earth surface must produce very striking
meteorological effects In all the over
shadowed region it must become colder and
the disturbance of temperature thus arising
must produce currents in the air-changes in
the winds. The chill in the atmosphere
might even cause condensation of moisture,
the production of clouds, and perhaps eventu-
ally determine a fall of rain Here we have
to make the important remark that some of
these events would happen during the actual
occurrence of the eclipse, others would follow
in a succession that might occupy several
subsequent days. A little reflection will sat
isfy us that the consequences of a meteorolo-
gical impression made in the centre of this
continent would not reach New York until
many hours, or even days, subsequently.
From this it appears that for correct dis
cussion of the effects of this eclipse we must
separate the facts we collect into two groups:
1st. Those that are observed during the
actual occurrence of the eclipse; and, I'd,
those that are observed for some time sub
sequently. The former may be spoken of as
local phenomena, because they are what each
observer notes during the eclipse in the
locality of his observations the second may
be considered as general phenomena, because
they are the aggregate result of what has
happened in other places, whether near or at
a distance.
Taking this view of the subject, l shall in
IL. i IL,
those of the last group. A few days hence [
shall complete this report by detail of gene
raj effects, thus giving time for those effects,
whatever they may be, to reach us at this OBJ
servatory. During the afternoon the sky at
New York had been very much overcast, so
that there were fears that the eclipse might
not be seen. AS the time of its beginning
approached, the clouds partially broke up,
giving at intervals an uninterrupted view of
the sun. At the middle of the eclipse, ten
twelfths of the suns diameter being then hid
den, the light was still sufficient to discern
objects at any distance, and though many
persons thought that there was something
unusual in the quality of the illumination,
others less imaginative correctly remarked
that in the twilight, ten minutes after the sun
had gone down, the aspect of nature was
essentially the same as at the moment of
maximum obscuration. The following are the
sions to be derived from them
Of tie IHermOm6ter.-At , p. NJ. the
thermometer stood at 81 deg. Fahrenheit
1t rose until g. when it had gained GS'25 deg
From that time it declined to 67'25 deg,
which it reached at ) o'clock, about the be-
ginning of the eclipse The fall of tempera-
ture still continued until p NJ, when the
instrument marked $3.50 deg. But during
this period of two hours the decline was not
uniform. 1t went on rapidly until the middle
of the eclipse, at o'clock, more slowly after
wards. In the first half of the eclipse the fall
of temperature was 1'25 deg; in the last half
only 80 deg. The eclipse over, the thermo-
meter still continued to 90 down, and at 10
p. NJ it had reached G2'5O deg. After that
the fall was much more rapid; at II o'clock
the degree was 1910. AS respects the
thermometer. this is the general statement
that has to be made There was a decline
during the afternoon, accelerated in the first
half of the eclipse and retarded in the second
OF the Ba1Umeta-At > p. NJ. the baro-
meter stood at 3O167, corrections being made
for height above the sea, caplllarlty, and tenn
nerature. 1t fell steadily until 4 p. NJ,
fhrouph ten thousandths of an inch. From
that Doint it commenced rising; and about
the beginning of the eclipse, at p NJ, had
recovered six thousandths Now it advanced
more slowly, and at 6 o'clock, the middle OF
the eclipse had gained only two thousandths'
Duripp the latter half of the obscuratlon the
rise was more rapid, passing through nine
tbousandtbs at 7 p. NJ. There was then a
fall. until s o'clock, through three thou
sandths. succeeded by rise of eight thou-
sandths in two hours; then came fetarua
ton. and in the next hour only one thou'
sandth was gained. The general sUaVe
ment as regards the barometer IS, that TINS
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