Year: 1874

audience who have collected TO hear the present VO'
OF lectures were able to attend the former couIse'
and that therefore ought not TO refer 10 matter IN 'o
former eoiures As though they had been heard let
fer h,s been received inviting 10 MENTION III 'ne
course Of these lectures the general iac's Ioi"'o "
transit OF Venus These would IKE 10 answer l" .0
first place It will be just to repeatflmpSNOu"S' i
instance That which gave before on the suns famy oi
p,apets having given q prospectus ana lectures
indicating that there would be certain NOVELTY IL
n,gt he pleasant but just thing to do ana AL
can say IN TO the request 10 tonc on ese
matters which necessary to make my SUBJECT coh
plee and 10 touch them sufficiently to demonstrate tho
facts necessary but TO make the subject so far as pos
sble now In regard 10 the transit OF venus thlhK
you have had enough of it. 1t Is not subject "men
orb,ps ,peealy inviting and therefore do not think
sba devote any portion OF the lecture to tho treat
meut OF 10.


gIIE FARTH'S CONTRACTION BALANCING ITS BETARDA-


TON.


II ,ems TO us 70 lie within range seeing certain
physca and natural processes TO that tae earth
will one dav be the scene of death and desOlat0n. One
OF these corresponds with the moons change in rota-
non by which it worked down until its period was
lunar month The earth has tidal wave, which Is act
iug "A brake and reducing the earths rotation
and will continue do until the period OF the earth
will be that of lunar month. You will remem-
ber that in the former course of lectures I dwelt
on that fact. l have since heard news
which will be gratifying for all those who may be
terrified with idea that in few millions OF years
that state of affairs would be brought about Prof New
comb tells that recent observations on the moon'
since 1863 show that the is running away from
her calculated place Some change is taking place In
the moons motion Astronomers have too thoroughly
mastered the lunar theory be in doubt about that but
certain change is taxing place IN the earth's
rotation and tnat is not Of the kind I have
spoken Onot OF retardatOn 1t is increasing in rate
Here is strange piece Of information, not the first
brought TO u.s. given by the companion Of the earth its
satellite the moon. 1t seems 10 show retardauon IN
the moon, and we know from that that the earth is
acceleratng her motion II shown too that 1t is not
uniform We can understand the retardaton Of the
earth the great tidal wave being opposed TO it; but
what are the changes which leading to this accel-
eraoni II seems to in this way. 1t is process OF
cooling Tie earth is gradually contracting, and
that leads to fastening of the rotation, and
that Fastening is regarded which counterbsances the
brake action Of the tidal wave Now it II it
more than cOunterbalances portion OF that but for
some reason other that change Is taking place more
RAPIDLY than any other. The rregulary then pro-
cess the interior Of that plastic ocean that lies be-
meath It ia curious law, but must accept facts as
they are presented to We thought the earth was
losing in its rotation, and now we 1nd II is gaining with


variable rate OF gain. and there is clear evidence
that she going to lose her rotation in any measurable
manner. ,,o. ,oDco he which tho a,r,b rrnst
gradually be drawn in 10 the SUM- that the ether
must compel the earth to travel more and more inward
until at last fall into the but the period s
go long that conception Is an lDnnly OF ume
ocsSpiS Sn space Prof WheWe studied Enckes comet
led 70 this result man drawing lul Dreath
in dIometer In order 10 take in as much at the
pressure Of Enckes comet he would be required 10
draw in a globe 6,OOO miles in diameter II We are to
have an atmosphere like that 1t must be period Of
millions of millions OF years. and we can hardly doubt
that that this earth will have ceased TO be me
abode Of fe SO that whenever the earth falls into the
sun there will be destruction OF life on the surface


MERCURY NOT THE ABODE LIFE


Now we will have the room darkened while we apply
these considerations to the various planets shall have
70 mention few facts from my former lectures but
shall take them for granted aud proceed to apply
them.


The panet Mercury is not studied under favorable cir
cumstsnces. When it is nearest to us Is presents
crescent shape. and when Its full front is toward the
Rnt We feel quite satisfied that it can hardly be the
aSods Of he such as we are acquainted with The sun
pours upon 1t with from four 10 ten times as much
fSs various sizes as seen from the different planets
The upper picture shows IL seen from Mercury here
be made Here we have illustrated before us the


supply Of heat poured % on MerSuT The Upon Venus mus
ture shows us the appearance OF the sun as seen
snU@ anoe from the asteroids But want 70 cali your
special attention TO the sun as seen irOm % 1upiter. &
the cause the changes there and when you see the
smallness Of the as seen there comparing 1t with
saturn that tiny cannot produce the effects that
ordinarily ascrbed TO chsnges OF great activity that





insignificant that would be seen there If 1t we're an
inhabited world


VENTS NOT YET HABTTABLE-CoNDITIoN OF THE


MOON.


Y,ass from the planets Mercury and Venus rapidly be-
cause we have 80 little telescope information of them
r, will probably dispose us regard them as intended
"a be the abode Of life but not yet Only when the
ba lost the fourth part OF his heat in the case OF
Mercury aud in the of Venus one half Will they be
tune viii come when Venus will be inhabable II viii
tnen be with her as with US now 80 we look iofWaru
millions of years when she wiz 90 nnaDeu as & ,ns
for short period ana not necessarily cotemporsheous
Here Venus. You Will see that there are CERTAIN
markings ( would call your attention TO the great
benefit OF atmosphere Of America In oDsery
ing marks. In England they say they can "aSh
large telescope Harvard and the other hne ones of
Alvin Clark and others fall TO show the Ing su9ect
that she shines with much light that tne eye is ue
ee1ved Three other pictures OF Venus Will be shown,
indicating on correct plan the decsey OF these
markings. We some signs here OF an atmosphere,
which necessary TO life There you see the twilight
circle Here IL becomes more marked and you see
there possibility OF fe as IT depends upon the ex
NOM we will pass 10 the planet are able to study to
the best advantage moon, which we used TO
regard AZ mere satellite but which is planet having
the zane path around the we have. We
ctOmed regard the earth as the ceulre OF the solar
she rs planet cirCng rOsnd the suD, having nearly the
same paIb as have. We Will now nave picture OF
the brought on the screen showing tne FeiaV1e
consider the diameter Of this lesser ORD ana u is ABOUT
the fourth part Of tue earth. The surface OF the
docs moi bear great proportion IL Is little more hdn
the ffieth part II assume that the same quanliy
OF mailer existed character on the earth
there will not the same amount for each square p0r-
so the oceans would nave been iess 81 ,h n
70 suggest that theory. la my Iast lecture SPOKE o
the changes IN our aimospuere' ina, az ndSt %
banjo acid, with some steam We Know tnht
ulfnuFa aelu