New-York tribune., 1841-12-30
gsgpr,ed for Tao Ne -fors Tf.ians-
Df. JaFdner'S Sixth Lecture,
Second Series

was made L. the forfns att cted hy the feathers OF
pird,. the ,aifs cf fsaes and the forms OF fishes
themselves Although it IS subiect perhaps
somewhat tfi,e. /, s never fails excite a GER
tan degree Of curiosity to observe the eStren'e!
beautiful manner in which the mechanism o' 'i's''
organized bodies i. found 1t Is recorded o' ''''
eminem preacher that on occasion he ooi',
menced hi. sermon by th. exclamation . goa
yba, {; f;so,oet,cian art thou which was followed
l., mos, beautiful and eloquent essay upon 'i'e
,ecoiar mathematical principles developed in the
structure n ,forsauz-d bodies aud IN many cine ma
,o,.l .ieet.. A, one ,ime during the last century
:. bo..,o. = problem Of no ;lle difficulty and Of
,..,,.id.rabe mathematical interest to determine
,be best f,m thlt c.u be given tile sails Of
viud.n 3, according 70 their VARYING distances
from the revolving wants an- hHrwi.c from the
centres of evolution. twill be recoi!ected that
the aenls icvo.ye in a plane night angle. To the
direction Of the wind. # is Obvious that if she
sails Ia position exactly perpendicular to
The arms the wind would ,triae them to any
adyantase aoa there would be no motion. By
placing thcm IL position patty perPendc cular
and pa,hy obhque, revolution would follow more
o. less rapid according the degree Of ebliquity,
somr angles giving velocity than oihers.-
The velocity wlil also evidently vary according TO
tne dsianc- Of tie sail from the revolving arm
aud from the centre OF revolution: the question
thus became very complicated geometrical pro-
bym. II. i. proposed to determine the best possible
position at every yaia ION OF distance and at every
part OF the arm. Af;er all their labored solutions,
,.nd when the best possible form had been attained,
it became evident that the result glaring copy
OF the wing. Of u bird, and that the problem had
long before becn solved b. the great Gcome;rcian
alluded TO b, the preacher have mentioned.
Another mathematical problem of considerable
difficulty Tor time was 10 determine the Sof'd
Of (eaSt resistance, as it was called: that /. to
determine The form which solid body must have
10 move through fuid with the least possible
rssstuncc. II is evident that if body, with It's
hat SUFFICE 10 the fluid be pressed through water
il will encounter yary considerable resistance and
The protcrn onga,rd the attention of NEwrUS and
the other ce.ebrated mathemaicians of his day,
10 determine tie form OF solid which should
counter ,l.e least After il had been solved the re-
suit she~cd that the form given wns that of the
fsh--so that the philosophers in solving it had
only followed in the steps Of Him who created the
6sh. In the tail ot i,h is also found an exam.
I,Ie of Art copying Mature; as 1t was found that
sub aqueous oar fastened TO the stern OF vessel
and playing in the manner Of ii li,h's tan, was Il
very ehcaci.us propeller u ship. The particular
motion required communicated 10y steam en- |
CINE You may rccollrct ai-o the resemblance be-
tween the leaves OF Ercssou: propeller, which ! |
exhibited a few evening since, and the tails o
birds
Another subiec, which should be glad to dis
cuss is that called Eiectrotypc. 1t was found by |
Sir HUMPHREY DAyY (and most fruitful did the |
discovery prove in his haud,,) that certain bodies
have specific attraction for tie opposite poles o.
d galvanic battery and from this resulted the pro-
cess called Elcctrotype in which by collecting the
1netallic element al these two poles form viii be
ATTAINED like a casting Of the particular object.
have been shown very curious model of this kind
by Mr. FRosI OF Brooklyn, which hope 10 be
able hereafter Ia exhibit YOU.
Another topic, announced in the programmes
but hitherto untouched, illustrates in remarkably
beautiful manner the way in which the various
branches 0. Science and Arr minister TO ench other
each receiving from the other ncxpeced
benefit. The history Of the discovery OF Iodme i,
extremely Interesting 1t VA. about the year 9l2
that CouRToIS IA French manufacturer OF salt petrc
! llink. found thai the liquid residuum OF the pro-
cess Of his manufacture produced corrosion of the
metal vesscl--which think was copper That
This proceeded from the action OF u chemical agent
he had ittic doubt; and he accordingly took II 10
:, celebrated chemist. NJ. CLEMESr. who, ON ex-
aminng ii, found that it was principle not before
known IN Chemstry-that ii Il substance new
ia him II proved 10 have certain properties bear
ing close resemblance To the Chloriues and in
some respects to oxygen. At first, CLEMENT did
nyt succeed in fuy investigating the problem or in
settling its ma,ure; and ii fell into the hands oil !
GAY LussAc and Sir HUMPHREY DAvY. The re-
suit was the discovery OF chemical substance not |
oniy new but sim ple-hat j., OF II substance not al
Jhat tiDie known To- be decomposnhlc nto constltu
.nt parts. By no known tests could ii he resolved
INTO two or substances this, in the strc, no
menclature oi Chemistry Is the meaning 0t the term
SIMPLE that By no hitherto discovered test it
be decomposed. although future discoveries may
prove i, compound. When DAvY and GAY
LussAc then discovered that Iodine was simple
substance, all they did was TO discover that it could
not be resolved by any then known tests. 1t was
taken, then, as one of the sim+lc substances, and
showed striking analogy to others, such as
Chromine, Brominc and Oxygen.
This discovery remained tor some tine the /,
surface of Chemistry-barren as TO any useful pur-
pose though Iodine was found have strong |
athnity Tor the metals, and TO combine ready with
various simple substances The discovery OF the |
principle, have said. originated in the process
of manufacture from sea-weed, which was used by
Counrois. He soon traced i, TO other marine pro
ductons, to sea-water saltmines, &c. 1t was ssos
nftcr discovered by an eminent philosopher, still
living nj Geneva Dr. CalNDEr vino had given