The Norfolk Virginian. [volume] (Norfolk, Va.) 186?-189?, 1895-12-29

portance of It's contributions to our
knowledge OF the physical properties of
the STARS. II has given us information
OF the origin and composition of the
heavenly bodies otherwise unattainnbic
and also of the velocity and pccuiiari-
ties of their movements.
The increase in the size and power
OF telescope object gla2.r.s has been
remarkable also during the half cen
| tury Just closed. In 1850 the largest
reiractlng telescopes were those at the
russian National and Harvard oLsrrvu-
tories. both of 15-inch aperture. The
object glass of the Icfia>tur nj the
LICK observatory to-day Is thirty-.iX
inchss in diameter, ana the one lately
constructed for the YerSes observatory
of the Chicago University is forty
inches in diameter. AT stations where.
clear atmosphere permits the full util-
ization Of the greater power of the en-
larSed telescopes their service in the
extension of knowledge of the heaven
is of high value.
In photography as applied to astron-
ohS Ing principal advance to he looked
! Tor is in the Increase of sen.itivencs,;
OF plates, hut ii is unfortunately true
that certain difficulties In the way nf
; their use viii! inevitably inca cas-" with
the constituencies TIE roggii. of tbn
plates on moonlight nights is already
so great that long exposure; cannot be
ninde with telescopes OF large angular
Aperture. and any marked increase, of
senSitivtncss will make II impossible
TO work to advantage in the vicinity of
Il large CITY on account of the illImiua.
ton Of the atmosphere by n,tiiicial
hight. II Will then be necessary To take
the photographs in places far from cen,
tors OF population and preferably mt
great elevations. where the renrc,in,r
atmosphere is diminished In amount
As To the possible enlargement by
no. ,l,,,.
stars known 10 us no approximate linn
1t can be fixed. Ii has been estimated
that rs many as twenty million dis
tihct stars viii appear upon the plant
sphere O; the visiblJ heavens when
conpieted by the Photographic rcnro-
auction Of al stars down To the four,
tcSnth inagnitudc. In the nvestiga-
tlon OF the planets, the application Of
photography is of comparatively slight
service. This is particularly Illustrated
in the conirastcd views Of Mars oh.
tanned from Photographic plat and
bE the drawings made from the tcle>
scopic observations OF this planet.
Oi the Invisible ana ;inmcasurahle
regions beyond the fart!;Lat reach Of
any instrument known TO us to-day we
can only conjecture by differences from
ne heavens within our range of view
II is safe 10 say. however. that there Is
no evidence that we are approachipr
n lmi: in our Knowledge Of Inc event
Of the universe
Upon some points of recent and c,,,i
ous inquiry aud speculation. Professor
Pickering prefers to preserve his opia-
ioiS lie visible stars are known, Ia
be of like character 10 our sun ana
may be centres of solar systems like
ours. hut the possible existence and
number OF invisible planets like our
earth are s:ll matters Of surynisc. As
10 the existence Of vegetable ana animal
lie in any of the planets there is still
doubt and disagreement IL not upen
controversy. By some astronomers il is
confidently maintained that Mars and
Venus IN particular are adapted to sus-
tain vegetable and even animal life.
Venus Is so constantly cnveloped in
clouds that observations are difficult.
but this planet is said TO be apparently
passing through conditions Ike those
OF our own earth years ago It's al
mosphere Is of twice the density OF that
of our earth and animals that may
exist upon II would be modified cor
respond!ngly.
The atmosphere OF Mars is about
one half as dense as that of the earth
and this condition will produce like
modification of any life existing on this
planet. That the surface of Mars is
s!ngularly marked by a number, Of lines
is determined by such n concurrence of
independent observations that Il NAV
now br safely accepted as q fac; mn
Pcrcival Lowell is still in advance OF
the majority OF astronomers In his nos
Tive conclusion that these lines are
stretches OF vegetation indicating the
courses of Irritating canals constructed
by creatures of high intelligence and
powers. II Is pointed out by the more
conservative Observers like Prof. AsaDh
Hal! that Mars seen through the tel
cscopc is relatively like the moon seen
by the naked eye, and the determine
ton of even the largest objects on the
face of the moon Is still difficult and in
dispute. as for example the question
of the existence of bodies of water on
this satellite ELIOT LORD.