New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1883-01-24


Ihave given this diagram 10 you once before but I
want TO call your attention 81 the method BY which we
ind the distances Of the planets from the san Ia terms
OF the Earth. You recolcct with The planet Verns all
we have TO do Is 10 hs angle here a. the Earth
S c y. at Tho mOmsnt Venus gsfs her greatest dis
lance fr0u tho IN few weeks she Will get a.
far wcst as possible ana then turn and back and a.
this point wo measure this angle. V Bs. We know the
angle TO os a right anglo and with these quantities.
knownwe can reach solution 1t DC done Jnsi the
came for Mercury. 1hsn for u planet outside OF
tho Earth you obscrye the planet twice oyer
You observe h at - and thea when b. ns gone around
tue yOu II again. AMI thhs md the dis'
find those distances before be discovered hlH mira law
lie could not discovered them without dong some
such geOlnetTcB work tnis. say ths DoCdu-' u II
said kepers third law gives rs the distances Det"eeh
the planets they eau be found witnont mt
Now, let give yOn Illustration OF me proportion
dstances OF the planets nom the run tho same
Irrschel .ed years which gives o good idea
dimensiOus OF the System. Take tho sun 70 the centre
ob0ut n, large az Grain of nustard seed al distance
of 81 festpretty well the end OF lhis We
would 10 "a pea distant ll2 ieet Ihc Earth W1u
be another pesf0r Venus and Earth very close
y allied IN size- dIstanoe ~ 30 feet Then Mars
would Do ab iu large the head of Glove al dis
tance O e0oui 3Z7 feet carrying II over across the
street rh-n should have a wider space, and
at a distance Of 800 10 800 feeC should u the
would come oeSt, at abort Union square, two ilths
OF mile away, aud az large az small orAnfe. then
Uranus about IS large az pu would DC encountered
hrcciOurhs o. mile way ANA Neptune anOtheT pn,
q
0ua Ter TO a mile and n third away down the Post
ONCE or up TO the Forty se,Oud Street DepOt ana ss
for tho ncaregt sar that would I've somewhere
Australia so that you the universe IA not
ALI aud there IL plenty OF room for the planets To move
in This description gives the true relation OF things
All the planets move IN the same direction, from
rRht to LETT you stood on the sun and looked al The
planets Won would them moving In "a direction the
reyetse Of The hands OF clock, and they all agree IN
that The old idea OF motion placed the Esrth at the
centre, the Moon next moving around ia CREE"
then came Mercury moving IN the c1rcnfnference OF
wheel aud the centre Of tho wheel went around
Had ayke
central curve the cycle Then followed Venus moving
the way. Tnen came the sun moving sbeadliy
around the Earth without any sensible epcycc mouoh
You what curious kiad OF path with reference TO
the Earth they seem to make. We can Of course
determine their motion in the sky by determining their
direction among the We also observe the appar
diaIneters from day to day. and sometimes we Ind
they TO aud sometimes that they retreat
frou. Then IL make a map of tue path followed,
we find sort or looped curve. The
motion is ooped motion of that sort,
and the sneients seeing that could be
compounded Of circular motion with another circular
motion on top of It, Put the planet circumference
of a wheel and make the wheel turn and you
represent It perfectly There irregularities,
however, that made them put wheel
and another at the edge OF that and sometimes they
get IA many three four Of those piled upon
smother-1rst a circle than epoycle. then an epep
eyole then cpl epereyele, and 50 Oh to the end OF