New-York tribune., 1879-10-30
HUDSON RIVER TOWNS.
RESULTS or SCIENTIFIC W0RK.

SESSIONS OF THE NATIONAL ACADEMY.
PAPERS BY PROFESSORS ALtxANDrR LE coNTE. o.
y ROOD AND OTBERs-cMIFORNIA RIVER Bids
THE AGE or MAN-MYMoRY or CoIoRs.
The National Academy of Sciences resumed
It's session yesterday morning at Columbia College.
Professor W. b. Rogers presided at the morn
ing session, and Professor o. G. Marsh, the
vicc-prcsidcnl, IN the afternoon. Professor James
Han, of Albany, y y. read paper on
some new and fahic forms of Crinod1 from the
lower Heidelberg ioruGiJ. after which the secretary,
Professor J. II. c. Colin. read laper sent IN
by Professor Elias Lpoms, of Na.e College,
in which he discussed tie comparison OF bar
oucicr ard tenn crature onseTva. ions at ON Fent
stat ous In tnc United Sfntcs. aud eSpe'l''N
az those IN IA latitude tue Atlantic aud Pfcihr
CO. .;s, and the Mi-,i--ip.i Valley. lie also iea"
pap.r bv Professor Asapa Hall. giving the results
o rcccut observations made with the great tclest"ie
m the Nlvai Observatory at Washiu sou, iiOm wicl he
de,ucrd ilu ln the periodic time OF one OF the
stars TIE laer was D, Professor stephen AlcA-
audcI OF Princeton. detailing very direct ana slht'
method asccrtuiug the ollipiry of tire terrestrial
splcrold involves observations at dis
tance ~ three or four miles In all dirrc-
uous from given station, aul dcdlcinf
from the curvature, the known distance and other
data equations ior the eari's diameter and in'i COM
parisun Of tine results thus Obtained. winch lhc Proes
-or SAID were very -accura's and readily oh
fe.~or slmue Z. Langley. az Alcsh,nv Obscry-
a-ory. Pennsylvania. criticised the method rs
liable practice to large mistakes tIIodsh rFes-
rir variations the strata Of the attn SPHERE
and gave hi experience in observing Mount I,ha
from The Palermo steamer recently. when ne saw dis
tlncty the upper 1000 Of the mountin at dis
tancc II 10 English mi'si at which distance thi-
" i,e portion of the mountain should, 10y geometueal
theory Invisible. great was tnc atmospheric DIS
urbance. Professor Alexander replied that distance
Of 100 miles not contemplated III his method ana
that the Desert sahara that mot brick al tie feet OF
Europe" produced atmospheric conditions IN the Med
ucrluean certainly fatal TO method requiring tram
qullity.
Professor Alexander read his second paper upon clos
ing his first. II the clucidaton hy means Of The
properties Of the triangle, containing two rsht angles
no less aud morc BY never 80 httic." OF tho
Theory Of Parallel Lines.
The afternoon session was opened by Professor
Samuel H. scuider ~ Harvard. who read paper by
Professor Joseph lie Conic Oakland. Ca concerning
the Old Rivei-beds Of California. In some parts OF
California he said. hnd where rivers
have been displaced by lava. and forced to
find new ch iuncs two or three thou-
sand feet below leaving detrus-hed channels high up;
wnilc in other cases. the old beds undere the new.
Some Of the new beds raversc the old and some arc
parallel them, cutting down below the
old banks Tnc mode of nllIng up these old
channels and the cause of the displacins
NJ form the most ulfnrul
vet important problem inCalforna geology. The Nuba
River has extensive deposits both sides. Under
draulic mining there been great displacement Of
gravel, disclosing the old beds. In the ma
teral found know there can be great
ridiiy erosion, channels three feet wide and fifty
deep having been cut In three IN the solid slate
Some OF material Is blue gravel congomerate and
bouldcrs; drift-umDer-oak aud conIfers-is found
mbcdded I'm the everything red material. In
the finely stra1ed sand are impressions OF
leaves and ferns, and also fossil animals That human
remains and implements found has been said. but
this is disputed The higher parts OF the country are
covered with tufa. basalt and lava, indca-
tive OF "A reeion once covered with lava and
cut down by erosion Several theories we're
mere propouuded account for the nng up Of the old
rivcr-beds and ali dismissed as untenabe except ths
th, was done by action. In other parts
OF the country Rivers run fast and cut channels
way are tue old beds, whose streams must have had
even higher velocity, filed upi II is because
every current, however swift will deposit II loaded
heavily enough with transported matier The erosion
is produced by neither too clear nor too heav
ry loaded, and when erosion ceases from ac-
cnmulatIon OF material. deposit begins Cases
are not wanting the nllng up OF very
rapid rivers. The Colorado and the Platte have
the same sOpe-eight feet TO the mile-yet the
hsn I'm the transported material The deposits in the
beds very coarse. and must nave cut iast IN
geological sense. when tue deposits were completed,
fhe strrams were displaced bv the lava floods.
Mere deposits would never dispiace the streans
.nev ana ice originally. but were released
nv the melting these by the approach or the .ubter
ranean heat OF the impending lava How. I'M. may be
objected savorng Of catastrophsn put the obiit
by nothing short f catastrophe. After the lava
came the flow OF ash ana me new beds
This lava flow from craiers, but from IFS
surrs and the side squeezing elevated the mountain
aen 50 Of fA beSs So% instead OF al above tne
Old We nave then the tor@a,ion Of the
.Ia Ar
the Cretacinn and Quarternian periods. with
neither much erosion nor muSn n ss w "os
denrs prepared for transportiug Inc melting snow
ran down in overOnded streams, alternately securing
ana rcillig. Then the lssurng Of the hgh sier1s,
lava Oberstiug the river ~ ste anu ASH lifue
,,n%. fo"yed New glaciers and rivers then new
,tyrrs showing preference for the old divides. The
hgh sierras naned and the lower coast
cisco New channels below the Old lava hled
channels and meteoric waters cnhged with nIne ana
sihra changed the slate and bedrock into clay
Professor Guyot remarked that this paper modified
ideas Of the antiquity 9i mSn. "s''n Gn' not Dc,
We fe our t for estimating chronology. and empha-
zrd the necessity tor caution.
Professor Marsh that the labors in this field
NJ Professors Whitney aud King, leading 10 different
tTot there is no doubt OF the Pnocene are Of
deposits in which occur human remains. Inc age
teese animals he should be considered a. Pocene,
al,o oO bean s 'mROfTh IN the Pocere age f me hSG
seen bastli deposits IN Plocene formations. showing
yolcanc action previous the glaciers. The animals
found tropical the rniuOcerOs and great soth,
and IN this time early man existed.
MEMORY OF COLOR.
Professor Ogden N. Rood. Of New-York, closed the
session with "A paper Our Memory for Color and
luminosity" giving the result OF a few expert
ments belonging to extensive series OF OBJ
servations which he has just begun. but inter
esting even st this stage Phy.icsts say that
while II IA possible recall TO mind distinct coors like
red yellow blue aud Others attempt recall mod
ife6 shades like orange bun gray. would end In
fni ure. Only fOf strongly marked color- Il the
ID he for !. N ~