Evening star., 1869-08-05
THE GREAT ECLIPSE.
Course Of the shaiew-Its Rate Of frav.

cling. kc.
The following extract Is from q copy OF q
letter written by Prof N. Springer, formerly
of the NatioLal Observatory in this city, to
Rev. Charles Collins, ID. D., late Preaident o.
Dickinson College, Carlisle, Pennsylvaai,. II
Tears date May 25. ls6i, and may be Of interest
TO our readers, as it gives important insorma.
ton relative TO the eclipse, which will occur
on Saturday, the 7th inst 81
"Since / came home have been Oueaeed
upon calculatians of remarkable solar eclipse
which will occur August eth, le6s, some eight
years be nee; remarkable for the great umoer of
cities and large towns where IL will be total: and
for the immense extent OF populous territory
in The United States where the eclipse will be
very largri inst Is, & where eleven disits or more
OF the moons shadow will hrst touch ths earth
in Northern Asia, latitude Sc degrees IS mia-
utes north, and Longitude lis degrees Is min
utee east OF Greenwich, At which point the sun
will rise centrally eclipsed on the morn,ng of
August 7th. The shade " then sweeps north.
eosterly around the head Of the sea of
crossing into Russian America q little south
OF behring's Straits. Here its velocity Is
about twenty Ave miles per minute. Hence,
SS1Nns sSIonDs Rsoa'nesstsrl{ , sweeps down
crossing velocity, ana enters the s. ate of Iowa
al It's northw corner, lat. Ask deg. N, and
Ion. s6A deg. ". 1t traverses the State in al
most q direct line, and crosses the Mississippi
river fve miles north of Burlington. themes
nearly In the came direction through Illinois,
which State il leaves at the northeast cbrner OF
Crawford county. Passing over the south.
west corner OF Indiana, IL strikes the OHIO
river at New Albany, which city and LOUIS
willie are directly on the central track. Tnsnce
through Kentucky into South west Virginia, II
passes q few miles north OF AbinRdon, and
nearly in the same direction through North
Carolins, II sweeps of into the Atlantic ocean
about twenty-five miles North Of Cape Fear
The central eclipse will termin ate IN lat. 81
deg. N. and Ion. 67k deg. w., at which point
the sun will set centrally eclipsed.
Ine above Is the line traversed by the center
OF the moons shadow. A breadth on each side
OF this line IS miles wide in Iowa and Illinois,
and slightly narrowing after wards, will be
covered by the shadow as 1t passes, including,
Of course, all places where the eclipse will be
total.
The velocity of the shadow increases, After IL
passes into America; in Iowa being at the rate
OF about IS miles per minute; In North Carolina
IL attaius q rate Of 20 mi es per minute The
central eclipse will enter the United States In
the afternoon, and will arrive at the folls wing
points at the times indicated; being the local
time at each point:
Entrance into Iowa at ih. 25m. D. m; crosses
the Mississippi into Illinois at Al. SIM. crosses
the wabash into Indiana at 5h. I'm; arrives at
New Albany, on the banks Of the Ohio, at sh
2lm; passes about miles north of Abin gdon*
at 5n. 3Sm., and passes on into the Atlantic ocean
The moons shadow. IL 1t could fall upon the
surface of the earth perpendic ularly, would be
circle So miles in diameter. but as it passes
ONeI tne luciineQ surface OF the edrtn, which
inclination increases after it enters the United
States, the shadow will be an ellIpse, with
short diameter Of S miles: the transverse
diameter increasing as the shadow approaches
the verge OF the earth.
This eclipse will be differently inclined to the
central path at different points Of its progress
In Iowa the shadow will be 100 miles loaS due
east and west; the course Of the central path
being east 32k south. The transverse diane.
Ter wings rapidly round to q conformity with
the central path. and in Western Virginia and
North CarolInaI It Lies almost exactly upon that
lire, having length Of iQO miles
In Memphis the sun will be eleven digits
eclipsed, and in the capitals OF the following
States there will be eleven or more digits
eclipsed, to wit: Kansas, Iowa. Minnesota
Wisconsin, Illinois. Missouri. Tennessee,
Kentucky. Indiana, Michigan, Ohio, Virginia
Maryland, Delaware, North Carolina, South
Carolina, and Georgia.
On the track of total eclipse in the United
States. are not less than twelve colleges besides
many eeminaries Of high rank, Nolik oppor.
tunity will occur in the present generation for
SO great q number OF savans In America to OBJ.
serve the various phenomena of total solar
eclipse. Doubtless the opportunity will be
duly improved.
-*On one of my maps Abingdon is placed
north, ana on another south, Of the central
path.