An introduction to astronomy: designed as a text-book for the use of students in college. By Denison Olmsted ...

welre the same in botll eases; blut sine tle attraction of a
splhore is tle same as though all the matter were collected in
the /enter, consequently, the weigllt of a body, so far as it depends onl its distance friom the centeir of fitree, would be the
squar'e of 11. 2 timeis less at the sun than at the eartl. O)r, puttintg 1W fbt' tio we\ight at the carthl, and AW' for the weiglt \at
the stitl, tihen
W':'.. 35:: 27.9 lbs.
t... 1.......
HI1ence a body would weigh nearly 2S times as lmuch at the
stril as at the etartl.. A lint weighingto, 200 lbs. would, if transported to the surfaee of thle s1ni, weigl 5, 580 lbs., or nearll 22
tols. To lift, one's limbs would, in' sucl a case, bt beyond the
ordinarl )power of the muscles. A.t thle sulrface of the earth a
body fttlls tlhrouglt:1l - feet i n a second; and since the spaces
are as ttheC velocities, the times bcilg equal, and tle velocities
as the frces, tetrefore a body would l fall at tile slu ini onO
second throughl:L -i, x 27A9&:::4::4t8.7 feet.
SO.LA.R SPo'rS.
1 47. The sulrface of tlhe sun, whlen viewed -with a telescope, oftep shows dalrk spots, whtich vary lmuch, at diffebrent
thlnes, il numtlber, fire, and extent. O)t hundred or morel
assembled in several distinct groups, are sometimntes visible at
once oil the solarl disk. ]'[he, solarl spots are commonly vvcry
smalnal, turt occRasionlSally a spot of enlormlous size is seent occup|ying an extenvt of 50,000 niiles or more in d(iamnetirt. TL.t}ey are
sometilmets \eveln visible to tile naked ee, when the sun is
viewed thlrough colored glss, or wilten near the horizon, it is
eell tflrotll(lt liTlt cloudls or vapo)C'. \ lWhenl it is'recollected
that I" of t thle sollar diskl implies an cextent of 4.100 miles (Art;.
t13), it is evident t that a space large etolugh to be seen by the
naked eye, must cover a very hti ge extent.'I 7 exhibits the appearatnce of solar spots, though muchl
too large coinpared with tlte disk. lWhenelver a spot is seen nlelar
the ef11ge (of thl disk, it appears ftelcshortet ed by perstective,
as int thlt figure'tt. solar spot ulsually conlsists.of two pamrts,.t1e tta/ttus and the ttm/bra'. The nucletus is black, of a very
ilrrgular shtape, antd is subject to great and suldden chtantgcs