New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1872-12-18

and that the angle OF incidence was equal to the angle
curiosity constitute the starting point OF our pioS'h
Pa OF Ineso arc capable Of the easiest experimental
fNr.raou but in tAc irs' phase I my DO 1Neu 20 ~
fcN Wors rcgi she so..ee y, I'm T. IN sli infert,
ana moses, the slow burning Of iron. lt develops
icit aujii the neat be preserved nsh ,enlera t
lautc Cable was probably due 20 he3i deVSi1lU ~ '.'
Wv Olrog metals are s more compustiDle man non.
y1 MAY LIGHT strips of zinc iu candle haule anu cause
tlel U burn almost Ike slipso, pt-l , l,ut ,,
coHns.on in the arr we may oiso nave
Ir.I Water. for example, contains stores ar oNlEtn'
VI. ch may unite with, and thus consume met" ,ia-
r 20 derive the heat aud light employed in the present
q.r generation merits moments attention Before
van L, In Instruments small voltmc bait fb-in which
Zinc is Immersed IN so'1'iS iltu. ~. me- ~ n and
90 0rv.r,n actual union, however, being avoided.
JauaI th- ,wo ends OF Ae battery by tncs wire, tNe
ts zine consumed, and neat as usual is th result -.
flc combustion. power which FOR want Oh better
name, c!d an electric current passes az INC s"i'0
ft.r. through tlC Wl.C.
Iae tGc timex wire in two, 7 unite tho severed ends
d. tiu one. 10 coWs win Nnte uea., " s o,,
come. fnst heatl lhe question h. well worthy OF an
answer suppose n te first instance, Waen tle Iuleh
Wac was employed. tlat we lsl $1,000 , MY, ne
continue Uuul 100 grains OF ENC Were colsle,'' ,o
I,o. aeccfato numerical expression. Let the ocuon
now continue with tns tnin wire kiVJTlng, " 4t
am1u.. of heat generated no the battery 20 INC
samc as boforsf No, u won.d ne les %. tse pr
t.. Do lact. by adding the internal heat TO the exc
fc' I'D, ~ m for to combustion OF 100 grains OF 1nc
s.nI ut ,l never varies. By this arrangement then
j. To- burn our zinc at one place, and 70 exhibit
f,. . arl l-.t OF is combustion 40 distant pace
B.. N.. IS. lor example, We nave our CRATE ana lue4;
l . I.l, ara h-t Of our hre may be made to appear
.f. ..u. We have here an illustration or the
.. lass t1, iu physical nature We nave lncessau'
.. ,re lie tam wiIa and attach to the severed
t-I... Sd. t.cE one Two tnu rods OF coke. on 0llng
e -.ts .1-eluer we OBTAIN a small star OF light.
o. lo employed IN our lectures Is q sluipIe
q.
f. ... Yi.a-ceJ uy 3D. Placed IN suitable camera
f..- o-- autso.e lcls' t1is AgA1 VIII give Us "'
....t . D. .cl, Oh ten cells stood on small table
.Y.. .e.. lie placed its poles an connection D.
...lc. On cutting it q very brilliant spark
...l le nal attached small carbon points 10
f.. end. aud brought them together they gave a
.- . .4ljgI Intensity. lie called attention TO ITS
4..i., which was psrceutioie enough, though
...,. .... ,i ID. .Jl o.. b; uuOTe .Ian sec0nd.I
OBJECTS OF TIE Eye.
-rr.-. u s.ing, let me refer TO the common de-
d. C. Gao g.O4as OF nature, the human eye included,
sac ..,aIo.Ic,l.y perfect The degree of perfection
90. a.y organ is determined by what it has 10
doc Looking q, the dazzling light from our large bat
tory r.r slo'c Of heh, bat entirely fan 70 see Inc
SD. .. r.e t.-o-nOlnfs whence thc light issues. The
,r.. ne tAl. Illustrated; On The screen before You
l-h. eo "a image Oh the carbon Poln.5, tAg
rhe luaso. 30 is not sharp, lut surrounded by
l... ... nearly uuiterltes IT. rms Il que 10 ah I'M
I. tLe lens, called spherical! alteration uGe ~
t..f .lt TIE CilCuul lrtItlal and central ry nave
Icons. Inc huIga eye abOrs under slmllai
t.. .-I Vlcu you looked at che naked hSht from 81
90 upon thc fetht was tll' 81
destroy t-e dlhut0no OF we Ictln"' ln"so VI ~
l.n-. 4 long iist Of indictments might hucod DC
mo- ~ ti- .acr cf achrCuatisln. is absolute blindness
o. l.lt. Al these takcn together caused an emlutn
M ir en- 30 f OF defects he would send IL back q
lm tl- scycrcs' cttsdIe' Bul 'le 90 g !, no, a.
rr'r.rr ana taking the adjustment by which its dc
l,etts 8eutrazed into account it must ever remain
ii. yy employed tie larger battery using the cleo
the - ms occasion required iu any one OF three O
... ns.l
c1.Estrk. The first image Obtained on the screen o
me carbon points looked like faint drawing ia BROW
tr.trI on a pure White circular ground ThO
c..ouar ground represented the gioDular hsh
seen ly tne eye Transparent screen wac 5Ien IN
seemed IKE twO burning yOcau0eS,0ue upside dow4 ana
ill., tr,v oyerhan giuC tine other when was coical BE
tvceu thern there space uiat looked Ike ~ Duft
iu- rs Of blast furnace where the elements "oHd
hr now We are ready for work The rectineal p-opa-
small no ~ EiadoU-snuttcI, before which stands "a
hone or rec. animal, ANA placing within tn dark
cucr room 90 white screen az some distance from the
ord.e. Livery straight rty proceeding IRON ne OBJECT
stamp ei0r upon the screen ana me sum OF an 5
rss ot. image OF TIE Object But o. tnc rays cross
crct paints produced by "a pinhOls m iufoil viii
h. cunloyca to illustrate this point OF retilnel pro"-
l each OF these images the carbon points were ar-
parent; tsy gradually Oyollagped each other as the.r
nGlIc. proximity was increased until the Thence
a.. Total circle o lat from the lens merely nc
Intricate au1 complete overlapping OF images OF the
SLOW PROGRESS or OPTICS.
T.e lav that The aug OF incidence is equal to the
ur c o. reflection is illustrated in this simple way;
Ar.-Lt lath is placed index perpendicular to
SINAI IooEng-gass capable of rotation. beam Of
u Is received upon the glass and reflected back along
fac ae Of Itr incidence Though the incident and the
reflected beams pass ia opposite directions, they DO not
i,.t. dis place each other. Inc index Is now turned
III. mirror turns along with IT, and at each side o the
index tne incident and the reflected beams are seen
tf.cuc tIcnselycs through the dust OF the ROOM The
ceion S TIC Two an s 9 SaT ea9ay T TRe
10
graf practical importance namely thal Wneh mirror
rotate, The angular yoiOCi Of beam reflected IRON II
j. tt.-c mat OF the rejecting mirror.
Id than 1000 years DO step was taken 10 opucs
beyond this law OF rejection The men OF the Middle
Ages In TACT occupied themselves on tAe one mana 10
tIgl- 20 teFelJp inc laws OF the lulFIso 1I U tcll
own cou.ciOusness while on the other hand they we're
80 OcC.Iled WIN the concerns OI Iutio Ia. nat
they looked WITH Oity scOrn on an tulhks PEI
so is only. As regards the refraeu0n OF hgnt, the
course OF real inquiry Sss res uihS', ~ ivO D9 M m
Philosopher named Amazon linen 10 was TAKEN up
H. succession 10y Roger Bacon, NitelIo ana keper'
One OF the most important occupations vi 81
encc is the determination Dy precise
81 the cumulative relations Of phenomena The value
Of such measurements depends upon Tue SKIN anu aDso
lute cOnscentousness OF the man WHO lhahes IneHl,
VIteliO WAS such man, while keplers habit was TO
ruage through the observations OF ms predecessors,
look az theln IN al lRhts anu IIls uis5lL 1 %
principle which united them. He had done ILLS Win the
asiroEoca measurements Of Gyeho Brahe, and had ex
traced from them the ceiepfdlou laws vi hSpI1 ~,
Bat the rcifacOn ne wac not successful Inc
principle, though simple one escaped nlh' ~ was
hrst discovered by WuleDOrd SMELL aDOut the year lo
Lcss WITH the view OF dwelling upon the phenomena IT.
self Of introducing 1t to You IN form MheI VIII
render nelhgble The play OF tbeOretc Thought III New
TONS mind L viii show you the fact of refracon The
aus, Of the and the turbidy OF liquid may here be
gass face half filed with water rendered barely tnrod
by precipitation or little astle is placed upon ts
edge viii glass vertical Through sht IN the
hoop surrounding the vessel beam OF hght Is admitted
Hpnges upon the water, enters H. ana tracks itself
through ne liquid IN "A sharp bright DahO' MtauWhhe
tie beam passes unseen through the air above the
water pun Of TOBACCO smoke into this space at once
reveals the truck Of the incident beam II the incidence
ne vertical lie beam Is unreffaCted II Obque its re-