, 1870-07-03
ORIGIN OF THE GREAT LAKES



ORIGIN OF THE GREAT LAKES,
lIg TEoFEFshA J. 8. SEwEE3R-,
The question Of the ons1u ct orr la!;os ia
on: That require. moro ch-crrati0.. su study
t ii, la,c ycf bean c;ve, 10 Il !cf no we c.u be
said 20 a.c solved Il! iae '!ia- i: inNol,eH.
There arc, bSwcrcT, certain fact. connected
with lho structure u the lakc baaills, aud
sonie dedrctios.s from these facts. wl,,cA Era
be regarded as steps already taken toward the
full understanding Of the subject. Thess facts
aud deductions are briefly as follows:
l. Like Superior !ies IN sync1ina] trough,
AID lis mode Of formation. therefore, hardly
admits OF question. though it's sides are deeply
scores, With iee-nsrks. and ita form and area
may have been Homewhat modified by this
Agent
2, Lake Huron, Lake Michigan, Lake Erie,
J and Lake Ontario are excavated basins,
wrought out of once continuous sheets OF
eedincutA,y strata by a mechanical agent, and
That ice Or walter, OF both.
That they lave been filled with ice, and that
this ice fortncd. great moving glaciers we may
consider proved. The west end Of Lake Eric
may to sad to I've carvsl out Of the eox..ifer-
uus 1imestons by ice action: as its bottom and
sides aud islands Horizontal. vertical. and
even osrrltarlging +slrfacts-are all fnrrnwed
lT E1acia! t:rooves. Which are parallel with the
major akin Of the !ake.
At uur great LIKES arc probably very an-
ciest, tts'cc tl.,. cla-c of the Neyoni.n re-
rid tho area they tet:lty has never been ssb-
yutIEe1 Lc;.catll th'. Ecs.aii. and their forma-
| tis,n 1nas Eave ltsun during the Coal Measure
| sl'ocL-
| Ii. Laurtnti.u Eelt, wliel, stretches from
] Labrador t" the Lake Of tho WooL-, and
! thence nosthwarl to tho Arctic Sea. fnr,ns the
oldest known porti1n CT the cartll's elrfnee.
The ehorcs OF this ancient continent. theu
| high aud mountainous, were washed bv the
~ - Al. =.
| Deposited III stsata that subsequently rose to
/ the surface, and formed broad low margin
| to tho ceut1a, mountain Le1t, just aa the Cte-
| taceoun and Tertiary strata Hank the Aucghan-
! ies in tue Southern States.
In the lapse OF countless ages. all the
j mountain peaks and cllaitia tf the Laurentian
| continents have lteen removed and carried III
to the eca. atl thir has ten done by rivers of
water and rivers of ice. That these mountains
I once existed there can be no reasonable doubt,
and it is scarcely lees certain that glaciers
have flowed down :hclr slopes Of sufficient
magnitude and reach 10 deeply ecore the plain
; viii, Il clscirLlr.! them.
Ii will 10 u.:;c.I that all tho grea. lakes OF
the continent Lull ccrtai. relations to the
c,,r,ng bolt of Laurefltan highlands
Some Of them arc embrace! iii the follinss
Of the Eoxni.' loclr. mud Il. rrncliaal nonGhs;
lut most Uf the series. f:nra t;reat lear Lake
to Ilhc Ontario, "sl:i?it the came geological
and physical -,rl,t.rrt. arc ha-iu- u cxcaya-
tim in Tue ra!eozoic plain ,hst TANKS in
! pi raIlel ac1t thc 1-anre.-iian asca- Few Of u
have anv conception nf :l,t. enormous gcueral
and local erei:'l' Which that Plain has safres-
cd Thosc who will take tho trouble to es-
amino tue section ar1oas Lake Ontario, from
tho Al!cGliaEics to the Lam cntian hills Of Car
| ads, and compare ii with the other sections III
the Lake WiHncpcg district, ralal 10 the L1u-
! teh..a' - sssen ~ Ut. il!u" u us lelof!
~ ~ tHe fe:.Dolh couhttF. WI bc suse 10 llnd
;ae eonlraaasotH interesting AUG suggest
Ne' shSSesHse especially Of
community OF structure and history,
~ ~ oi an lhsspaf@ap!e @ eonheetioh Detween the
!ahe l'neisnnGna anu tho topoEfaGMcal Tea"
.L .It' =. ,ilg i.aate''''an n'5t'ancs Aankeu %
! 'I9 nt11o.G l.;nso,; l.air.
~ ss,'ma',nS ~ tI'e Iaaaenees !ha, mlSh, nave
tc sSs ~ ~ ,s anu o,m. o, =
% ths s'o's q 'as a.au1eittaaa n'o!lhselhs, 1t
rnoulu NY ~ oiuisuteA tuaa NC IEetaeeous
sea s"el1 wy Westc.M s!io3e OF tne Aaieozoic
a,,u !satte.a, ~ ~, cnsuacn. rom 'lla t,ul. OF
! AeA.o 20 wv iNeltI cceau' aha "netnes We
eo1hldef nus sea as broad e1panse OF water
slME,! 1oIsu WIKI islah4s, ol etEalt
,ta'efseu n tropcA cutfcat, We
HaEe ~ estnet ease cohainona pectni.
AIRY 1asorahiS 70 Inc lofInatien ~ great glacial
h!Arses y. aet, !. :. otoaa esApoEathe suriace
o1 Wa1h wafer sWci,, =! Westerly "1nas mat
easneu az sasGeh!ea moisture i;nsnealatel? On
cc1.aclis's, -.,
lEs. II !'es8. may be 1nE1t1ve.E asserted III
r.Ean 20 t''c aeehes ni lrc u the excavation
ef t:' lake easinH, HAT their bottoms and
La.cH 'Ae..sGr 's't'sed to ooh:cryation. il COM
I.l osed of resistant materials, hear iadisru-
s r W,a,, fIf, action, proving that thcso
.us: ie ,r1jc,} Il tnyer |,cf AMI fl,,} fa4e as4e
! a. 1r:,t' at t1Ie cro.;on hv wlirl, ,t,cv ,rcrc
Toned is due to these ciacirrs.
M other agent tlap ciarial ice. nj If sec.ns
f., rrc, il c,ralle Of cxcavati,,s broad. Gcer.
lr s,rhane,f basins. like t1,osc ,rlrl i,o,d ~,
likes. WA
n th,, f1cr,t;on ri t.n,ncr,tr-a mn, ,o,ro,+
rortl,warr of lie ,.,,r;cr. ri tIa lila 11,s,,s
wr,e Gtt Uniform tand co,tiuuons Int al,crn.
atcl with rtriMls Of reno-c. W. shnnlI finf]
.,cI IT mb;'.,, wnnii acyso ~ n,a,.,,ta us'In IT.
rr,arh nf Tia ,,ar;ar ,t ti,o t;,nn ~ ;ts far,n.
,ion. lie iuwtst basin ,,ins I'll thu " oiies, ~ tho
..,h"r,. So,1n",f j., 1,n.assn5 ,tt. ~ ~
s'n.,s ] IN l =, ss,
local csna:,s;,,s If ti,o tro,, .bs ~ ,Ie I'll ~
Wherc ,.,,ricr. f,ov ,o,zn f,o,, ,.,,,,,,. m
IL n ,l.;,s nv !, 10 t,,n 10, ti,o n,rrr.t;. w.
,io,, II II H.. MAJ n,,,.t t,r-,;,,t"
MINI al,1,nsir in s},c forn,,;on ~ t.sir.ik,
! ca,;tv. Lo,on,l Will, wmiJ ha . y;1, ~ rocE
viii, whatever of ,lbr;, the rIarier has hra,,rh;
When ,.iaIcra reach tin 70, ,.,c crc,,
", ;rl,t or IT,. icr ness ,nnst ,,fow mn th, So
i.,ttnr, o,,t ~ .a ~, ~ ,,crc t,,p or
c1av;tv m ra,ar 1;f,s m :; - f,a,, ;.s ,,e, a.;
So.,a !, a.av ~, ,ca,,cr,, '7 0e1' A'>
r. n is tr;,r M tl,e fnc,s 1h,ve citsl indi.
<ato t,,a. mr. III a. arc Int n,rt;,rs ~ ,.rr,
.1.ayated fl.,uc1. 1ce.ly f;1t,.1 wt;, ,lrift M.
tcr;al. III. forls Of The iio, thcrn atlantic a,,i
l'ct;fic cuaet ,rcse,.t re,narkahic na-allc,s +,
:hrrn AM, I wm,1J .nvrctt I.urcs;s Smn,i
Uno,ls Cnn,l nn,l nt1,er nortinns If thnt wnu
tlerfnl srsten, NJ nay;,.a,,i. ri,:',,c;s ,l,om
Vanrr,nycr's i-|,n1 ~ ;, ,fy,,,,1;,,,. ;ntc-e.tfn,
ard instr,rt,yc xnl;c,ts f,r con,,,,rison. III!
| our lake. tbcir ch.,:na., arrIfnr ttc mat mar
errayat, Il fIn,u sci,ncntary rtruta ,s1;ri, fnrn
law n, ,r,t,tars,,ivei, 1.y,; ,n,r,.;n T., III,
s.asts ,.f mountain claims % and nesIs' T1,cr m
I Inn have tic;r ,l,1shs a,u1 .h.1tn:,a thcir Ia
ris MD lsr,, AMI 1'rnlaI1r ali via ,,,rn ,cc,
4 thcm viii nr.,,n, +, 1,rnf...aor n,n,. v;cw
that they AZ. ti r,,,l,i, ~ sns,ssrisi c1c,rs
ZION In wi,;rb ,.,ac;rrs ,,arfnr7n..l au ;mnor
tart mart 'se'
Tlt :" in,.s 7f ne ,f;ss;.s;o,i ,-on7, TIL
"lluff formation NJ thr Wat som.tfIne
c,iIe1 - ncss, FINN H. re.cn,',s,nce ~ n,
l al T =
Ss.;as,..t ~ .s is.S, Eate ois - ~ 'aS
! e;ee =. ~ - ~ ~ W.. : 'ae ~. ~ =.
tS ~ s... ~ -. ~ " >ae eeGai ttSea..'a
.ea IVY .Ie Satcis " oaf bseat nita'ti so y
..s suatoN aIa iliole 4'let l'a1tsois, 20 "1ic
eetelss, via 't:e's bIa'et anu boa'iets. la
no aeEcs9. a'u "Ar!e tte e'3;!al muti WIS fel
, tsseue1 wy y sn nnl'2'pa"'e l,D"ue1. |lue,