New-York tribune., 1876-02-05

suits to the study Of few hurricanes. Inc mathe-
matcal formula by which he has endeavored 10
show the relation between the velocity and pressure
Of the air and the dimensions OF the whirwlnd, are
apparently deduced in not very rIgor"us'
but sufficiently approximate manner. VI hp
plying them to the actual obscrvatiohs t,S,1 taSo1
in connection with the hurricane OF do3o 70
Cthe so-eaIled Antiguan hurricane), and also 20
the hurricane of the 2lst of August, ls1l he nnus
that the formula represents the observations WIN
degree of accuracy probably within tne errors W
which the observations themselves are llbeIy 10 NC
subject. The simple principle according TO whch
he ~ able to calculate the nature OF the hnai snap
of the surface which Ia shown whenever water ~
allowed to How out of bowl through central hoie
consists i'll this, yiz that when tho rotation IL once
established i'll the water, each particle describes
circle about the central axis, whose radius ~ sich
that the pressure of the wafer above the moving
particle exao,iy cuunterbalances the centrifugal
force due 10 s circular rotation In the case oil the
atmosphere We nave instead of well-deiined sur
face, s1Ios OF surfaces of equal pressure, and the
centrifugal force due to the circular movement
around the center of the hurricane ~ conntefnal-
anced by the pressure of the atmosphere at that
point. Unfortunately, Mr.. Colding seems not to
have taken account of the force due to the rotation
of the earth Its axis. liz equations, therefore,
apply tn tOrhalOcs and 10 the central portions Oh
hurricanes better than they do to the exterior por-
tions of large storms.
NrcKEL-PIATING SoLUuoN.-IIesz prepares n
nckelplatng solution that yields beautiful results
by mixing the liquid obtained by evaporating so
to pasty mass, and dssolving it in one pound Of
aqua ammonia with that Obtained 10y treating the
same quantity of nickel with 4 solution OF two
ounces of cvanidc Of potassium IN pound OF water.
More cyanide of potassium renders the deposit
winter, and more ammonia renders u grayer.
New SUBSTITUTE FOR BARK IN TANNING.-The
Western Tannn Plant (PoIWonWm amphbium),
which grows ltxuriantly in the Missouri River Val
ley seems destined to replace 0ak bark IN tanning.
IL contains Is per cent of tannin, while the best
bark contains but ~ per cent and large establish
ments employing it in Chicago find that nne-third
more leather can he obtained with IL than with =
like 0uantIv of bark The process 0f tanning with
il is 'cntiSl with that with bark, bur the leather
is tougher finer aud moro durable, aud receives n
finer finish. The plant is an annual, and can be
moved, dried, and stacked liko hay.
SrXpuAx07'ruos ON SUBMERGED PLYrs.-pr.
Pierce has observed the rotifer known IA the
Stephanoccros growing OIL submerged plants near
the Schuylkin River II had not been previously
noticed in that region. Dr.. Pierce found that it fed
on paramecia, which it seized by the eXtsemitics of
its horns and passed tO is mouth by movements of
the ella which cothc them from apex 60 base. Thif
StepIauoccros is incloScd for much Of its length in
an iuiIcxible sheath but at stated intervals the pro-
rctcd portion separates from Ills Sheath. and SWIM
ming {" another locality locates lt'e'i hN ;ho paS''
This D.. Pierce ohscr ryel t. take pl ,,. lnrs
lie never saw auy fr,al Discharge. from the anli"a
aud suggests On IN" solid case j. formed nom hon.
and that the mirrajloh ~ t'r N''Pha"'rto' - "u'
o the hnal obstruction IF fins means OF deposit.
Nrw d D.TrRNINA1IOS oF rHE VELOCITY or LiGHT
Some esp 'riments made by Conu in measuring
the yclp,ity Of light according To the wcll-knosn
method of Fizcau having been quite successful, lie
obtained the means for rep atIng his determination
by experiments upon n much larger 'calr and his
final results are Of much vaue. They obtained
by MS selecting for his two stations of observation
the Observatory at Paris and the tower oe Monte
how which i about IL miles from the fornera dis
iance very correctly determined hy geodrlc opers-
iions 4 telescope Sationed at the observatory
Of 27 feet focal length and inches aperture The
rays of ieht passing through this TELESCOPES emerged
aS bundle Of parallel rays. paSseI 10 Mnn'l"hoy,
were there reflected, by a plain mirror, directly
back on them selves. and cnnVcrgrd again to p"int
At the focus. Il ,-e to the place Of their origin Tho
which the m .asu-'mcnt OF tic velocity Of
ligh' i, made consists is thi' that ion'hed wheel
rryolyin with great vclocity. alternately cut, of
and allow, 10 pass the original beam OF light. II iu
thc timc which the light occupies iu passing to
the distant sta ion aud back, h Whc has fcNovcd
far around ls axis q. to huug one al - lr"h 100
H.. pllc, of at interval h-tW""u the teeth through
which he ray of light originally slipped, th r tc
observer looking through. will ind the beam II light
Invisible, ~ being prevented nom entering MS eye
by 4 e. Intervention ~ tlo tooth 90 qufsfo. Iy
means f a chruuougph. the observer makes
rr,or from which We can determine TIE actual We
l1cIty Of c revolution of o." wheel la the present
case ID WAS fpuld thIt ~ required about ia" IIJpD
paf! uf second for light to PISS Owen th' iuic sal 90
aestiou of about 30 miles and the actual velocity
= light WIS d@inced at about l2fooD niie' SC
ond This velocity Is that " Ia u b. peculiar 10 ~"
massage # li"t through the air, aud must hc multi
ilicd b. tc 'oHcicg's # rciraclon ~ ~" atIlo,-
pliere, ia ord TO obtain the NeleIiy oi hight in
a. q fr lts.T Z
300 u,srIy.t ons, j. given 10y tOiiu as 100, 700 hil-
omrters or lsG. 800 Eneli-h statute IA les In com
bination with the alteration oi hGed stars h" de
dUcrd the distance oi the run 40 corresponding to
the par,llaX of S.sS".
THE MoNs9oS.-In the magnificent volume Of
magnetic observations at 1rcyandruin, IN Southern
India. Mr. Brown gives the following interesting
account Of the advent Of the monsoon. He MAS
stationed at certain times at auxiliary obscrya-
tory Oh the peak known Ia tho natives IA Agu-tia,
whose altitude il over 5000 feet and which from
time Immcrnoral had been superstltously regarded
by the IIindoos ~ the residence Of Agusia savant
physican philoogist, aud thcolociau, whose pfiuci
pies were celebrated for their purity Mr. Brown
states that during his visits to this peak ho mad
daily notes Of the appearance of the clouds and sky,
and that there is no place in India where thc nag-
nifcent phenomena which prcccdo the bursting OF
the monsoon can be seen and studied with more
ease The peak in question is one conspicuous for ts
hight and is isolation. AZ seen from Treyandrnm,
it rises in the form Of sharp-pointed cone. On the
west it is PERCEPTIONS wall for nearly 1000 feet,
and on the east it descends at angle Of about G0'
with the horizon. Standing on its summit, for
month orrnorc before the final crash Of the tempest,
the whole operations of the great atmospheric
laboratory are developed at ones feet, while the
summit of the mountain itself is rarely visited 10y
tho storms which rage over its western ianks. On
the occasion of his first ascent Mr. Brown states
thai. arriving at the summit. he saw to the west
Treyandrum lying the low lands, the internc