The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1868-12-31
TIE EVOLUTION or THE NORTil sNERsG An
CONF NENE.
Lecture b, Professor James Hal,

Lecture by Professor James Hall.
Another OF the series or lectures course OF de-
livery before the American Institute was givsn last
evening at Stetnway Hail. The lecturer was Professor
James Hall, state Geol0gst. and his subject was
1.-The Evolution OF the North American Continent
Tie hall was fairly filed Ivy an audience composed
both OF ladies and gentlemen. At the back o!
the stage were hung number OF dia.
grams representing the North American Con-
tinens. 40 coored to show the different geological
formations and to these the lecturer frequently
drew attention-so often, indeed. that II is difficult
tn report his lecture without their aid. In his open
ing remarks the Professor INDUCED iii general obser
vations the formation OF rocks and the shaping OF
pebbles. sand he said, was composed OF the harder
portions Of these rocks which were separated by
trituraton--the finer portions going away with the
water by which they acted upon. The various
strata formed by the action OF water or by the
action OF the surface OF the earth. The northern
portions OF North America were composed prlnci-
paliy OF sand, clay and limestone which were,
IN fact, sedimentaly deposits, Or in other words,
belonged TO the mctamorphic era. The East
abounded IN fossil shells and the West belonged 30
the caeareois formation. The eastern portion be-
longed 10 the Dcyonian formation and The rocks i'm
that division belonged chiefly to what was called
the Hamilton group Of that formation The class OF
shells which were found were biyave, and belonged
Snore. In the cacate0us matter In the valley OF the
Mississippi different fossils were discovered 10 this
formation followed the carbonlferous winch was
known in this country and III Europe a. that in
which coat was to be found. fhis begin
Nova Scotia aud extended southward the
United states. This formation was evidence
OF tie presence or dry land us plants could be dis
covered deposited in the coal region which could
only flourish where there was dry land. Ths, en-
croacDment OF the dry land commenced In the north
cast OF the Continent and caused an alienation OF
coal with SANDSTONE and in some places limestone
a % Ia md prn-
ceeded to Missouri and even to Kansas and to a
small degree beyond IT, The great coal formation,
now svcr, came rom the Northeast Westward there
was to be found limestone only, which had been de-
posted beneath the ocean and which yielded
marine ANIMALS. The question would be asked,
how came these deposits, which
made below the water, 10 become airy lsnda
The answer was, the Continent began 20 be dry land
at the carboniierous period. There was 40 especial
disturbance to raise the dry land above the wafer;
WAS Il gradual change winch gave the eastern por-
ton OF, the Continent the appearance which 1t now
had. Where deposits over the surface under the
water had become very thick IN increased tempera-
ture in the interior had al last so heated the deposit
that II had expanded the entire mass There had
been no breaking Of the crust; 1t was simply the
action OF increased heat on solid matter, which
according to well known laws. was sufficient to ele
vate this portion OF the country
The lecturer then drew the attention Of the audi
dence To diagram representing the hills and val
ieys of the Continent from the Aeghanies to the
Delaware, together with the position OF the various
strata, which had been prepared by Professor
Rogers He claimed that the strata were originally
In Il horizontal position but that now they formed
mills and valleys, which was to be accounted for by
the piling or layer upon layer, so that in some
PAGES depression ana In Others elevation ensued.
The folding Of the various strata the result OF
gradual depression. Take number OF sheets OF
paper ana 1t was impossible to depress them In the
centre without causing fodings To take place. The
cooling OF the carths crust had been the cause to
to produce any folding. The Continent, he
again stated, was not giyea Its form by
any the w onr %srs Aq Range ssS Se
various strata were 10000 ieet In thickness. While
the Mississippi valley, including the siluran. they
were Only 1.O00 feet. There was material to make
the mountains II they had only been elevated
portion Of tie Continent which mad been elevated at
paratvely not higher than the Mississippi plains
The mountains were, In TACT, lines OF deposition
and were originally the lines Of transportation Of
the heavy materials beneath the bed The
western portion Of the Continent had only recently
arisen fiOm beneath the ocean, ana the CONT
formed from pre-e&sting continents. BEGINNING
II the Northeast. the slurian, Deyonan, car
boDitegous ANA other strata had formed the West
ana the Southwest, which subsequently were cie-
waited and 81 formed the Continent. There were
tceabie thee great periods each or which
marked by u chain OF strata. There were fossils,
too each successive bed OF which contained a chain
d fossils from The base OF the siiurian 10 the Dcvo
man periods. AS In this day, one FAUNA gave place
to another, aud wnen IL was remembered that these
animals lived ana died generation AFTER generation
and other species came m until hundreds OF feet
were spread over by them, it Impossible TO cal
cuatc line, aud AN lncomprehenslble number Of
81 ces we're created through an almost indeaniie
Previous TO the deposit oil the materials which
formed tle North American Continent there must
have been granite and other strata OF rocks which
were broken down, transported and imbedted IN the
ROCKS OF ths country. Beyond what could he seen
there periods OF stratiied rocks which had yet
10 DC discovered. The geOl0sst had no knowledge
oi the primary nucleus which ~ the action OF water
naI brought Lte sediments from unknown sources
The nucleus 81 melted matter had never yet been
found. but h was known that tine North American
C0ntIunet had taken is form and material from
tle bealing down OF prc-oXisting rocks, ana
tnat where these deposits were spread out IN MD
ocean Their elevation was due 10 no special action
u 0ng the lines Of elevation, but 10 the growth OF
"a ulaliOn aiOng such lines. The elevation was, in
i,Ci, 4 On'ucnlal one. There evidence Of
any rupture from the Interior which proouced any
alteration IN the form. The primary nucleus was
only matter OF theory. Nothing was actually
known about 10, but II was known That the currents
always set nom northeast 10 SOUTH and the evidence
to the formation OF the North American Continent
was All derived rom knowledge OF the transport
Ing power or these currents.