The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1850-08-26

Inc speaker remarked tndt Professor Airy does
Dot consider this gradual progress of the axis of
thu ellipse as precisely correct representation of
| the case but the moecule should be conceived to
vbrate many hundreds of times in one and the
same position, and then hundreds more in a new
position, and so on. Ii is emily necessary, then, TO
imagine the ivory ball to vbrate with such rapid-
ty as TO make few millions of oscillations in each
oflts successive positions; or, TO state definite
case, let it vbrate five hundred thousand times in
each angular second of its progress, and yet let the
ellpse Of vibration make its entire rotation in the
one-thousandth part of a second of time, still the
whole will not be too great for the truth, since
the number is six hundred millions of millions per
second.
Professor s. also exhibited another article az bis
invention, by which the lecturer enable his au-
dence all al once to try the experiment of compli.
mentary colors in vision The apparatus consists
oftwo discs, a foot or more in diameter, and per-
foraed by three ope nngs, and the other behind it,
painted with alternate white and colered sectors.
While the hinder disc is so situated as to show the
colors through the apertures the spectators look at
liked point the front disc till the eyes are lit
lie weary, when the operator suddenlyremoyes the
colors, and renders the whole surface white but,
instead of appearing white, the three apertures are
seemingly occupied by beautifully dilute tint OF
| repeatedly and successfully performed.
On the results of the discussion of the Tidal OBJ
servaions, mede in the coast sarvey at Cat Island,
in the Gulf of Mexico, by A. ID. BAcHE, Super
I nteDdent.
Professor BAcnE, President of the Association,
stated that the tides of the Gulf OF Mexico present.
".
| not universally, single day tides. Those at Cal
Island were the type of this class. The discus
SONS applicable to them, reduced TO rule, would
answer for all others of the class. The progress
| OF such discussion he proposed now TO present.
| The tides at The entrance OF Mobile Bay Were in
! part reduced, and new observations making there,
and at other points in the Gulf BY tn. kindness
| of Col. Albert, Major Bache, Lieut.. Msury, and
others, access had been gwen 10 observations on
record by officers If the army and navy The
coast survey VI uId necessarily in us progress at
ford observations for the complete discussion of the
| tides of the Gull Of Mexico.
Prof Bsehe gave notice Of the place, means
and manner OF observations, Of the persons by
whom they were made end discussed The OBJ
/ seiyatons were made hourly, day and night for
year, and very faithiully,by Messrs. Windeman and
! Bassett, under direction OF Lieut. g. p Patterson,
OF The navy. The average rise and fall is but
foot sIhtre Is one high and one low water rule,
IN The twenty.iOu hours. The wind is supposed by
navieators generally 10 cause these tides, but the
bypo'h,sis' when carefully examined, falls TO the
! ground.
Such tides had been observed elsewhere. A
| brief mention Of The explanation of Newton, a no.
tee Of the researches of Mr.. Whewell and OF MIR.
| Airy followed. The reductions both ia tables add
diagrams were explained.
The time oi high water advances es the luHar
day gains on the solar, until suddenly il shifts rine
ten aud twelve hoUrs. The low w5ters follow the
! same law. The times OF change are At, or
7 the period when the moon crosses the equator.
his points 10 the diuInsl inequality, shown 10y
Rr Wbewell, as the source OF he phenomena
obtained by considering the uni-tidal intervals for
the superior ard inferior transts according 10 the
moons place, north or south OF the equator. Ord
l nary modes Of discussion fail obtirely.
! The curves of hourly observation for the year.
leave no doubt that the declinaton changes of the
/ moon Gre these first 10 be locked to. Ordinary
ooublc, or six hour tides, occurred always ~ and
near The peilCd OF no decliuatOn. when they were
| ntar the quadratures The tables for the whole
! year showed this, and the comparison of tides at
The zero and maximum Of defamation showed that
| The TINE 81 the occurrence (epoch) coresp0nded,
/ very nearly, az a mean with the moons position.
The explanation OF the tides 20 be found IL
the interference Of the semi-duynl and OF the dur
/ nal tide waves,
Prof Bache examined the interference Of mean
| sem diurnal end Of a mean durnal curve apprOXi-
/ naiely deduCed from these observations, aud
showed that the coincidence Of high water5-a diff
i,teree Ct three and OF six houis-would not agree
with The observations, ana that difference Of ainc
hours represented II either exactly or nearly so.
/ lie traced TIE variations in foim Of the derived
curve corresponding 20 different decnaiiOns Of the
/ moon ard % different Thascs, md showed their
| general agreement with observation. lie gave the
| form Of equation % modified fom Mr.. Whewsl,
/ and simple result Of easy tabulation ior the
greatest cidiDale.
Prof Baehe rhowcd how the curve OF observe
rCn could Re dscomposed into two others, aud the
Elon followed for thus tabuiating the observed mum
bers in regard 20 height. The curves thus afforded
were tested by theory, and gave results which were
accoIdant. within very small quantities. The great
ct difference Of the me N Of three months Obser-
walton, thus discussed, from the theoretical stan
taId, was but Three huudfCths ot g foot Extracts
from the tables were shown to the section, and the
rttults represented on diagrams by tracing curves
OF comparison. Should the further examination
CO.. firm these conclusions, the two tides can b.
separately obtained from The observations, and die
Cussed according 10 the human laws Of lunar and
Ogr action This had not. 20 far az he was aware,
been done before. As far as the work had gone.
the results were very encouraging, and gcemei 10
Justify the labor encountered. Prediction tables
could rot fail 10 sd 10 results most useful 20 nav
CATION, even II The full requirements If theory were
not met ty the pfcsen. hypothesis.
srCTiOS oF oEcrCCv ND vArJrkr HISTORY
On the Position end Character Of the Repilian
Foot prints ia the Cafbouerous Red Shale
Formation Of Eastern Pennsylvania, by Pro-
fessor II. ID. Rooms. The Professor bsran
lis communication by stating that the an
Gent foot prints first discovered by Mr.. Isaac
Lee, Of Philadelphia, IN the red shale forna-
uon a. Mount Cafoor, ia Penney iyania, ans -.
signed By uhat gentleman to the red ks Of the
Diycnan period, belonged truly 10 the carbOBlrrous
red shale, and ere. therefore, Of sge essentially
later than ihat siirihutsd 10 them. They occur,
ineeed, m geological ho'izon, only Few huaircd
leet below The cCnaloJEora.e which marks the be-
ginning oil The productive coal series, "a which
series fimilsr foot Ifnis, attributed 20 Bairacian
reptiles, had been previously met with in Weaie m
PENNEY yanis. IHsioad, therefore. of constituiing
register ct The antique hfe earlier than any hiher-
20 discovered, by al least n whole chapter tn The
seoieeical boob, they curry back iis age only oy
single LEST The surfaces upon which these in
icfesting foot prints abound, are the smooth diy.
sicnal Plains separating be beds If red sand stonc
end exc invariably coated with q hae impApible
matefisl 20 a once Shiny and soft mud AMI every
thrg in The texture OF these surfaces, goes 90 prove
thai they were in contact with the ar. and we're
Tie sigges q rest between the alternate depJsi.
iiCns % the strata. Many Of them are covered
with urle lines snt wafer marks, suggestive Of
the shelving shore, and with few exceptions, uhey
ere epuited with little circular impresfion inn
rIied 70 the paitcfing Of rain. All over me sue
cctsive ilcos q the living world, delicate and
impress bic In their texture az 90 much wax or
parchment, are the fo0'aicps and Tie trails 81 W.
fiors creeping thing the prints % some W.
known Tour i0Oicd creature, thought o. I've Iepuiian
IN It's nature but Of whose true aihsiies the pro-
lessor expressed his doubts, tTsus analogous to
those 81 worms end muuscs, and various oiher
marks, write IN heirOgly phic is too scent 20 be
Hitfweied The larger foot ,nnts sre for the
most purf, 6ve.teed, altefnstr IN the s.ap. and
w u the fore frcf a. large neprv the ltnt tns1.