New-York tribune., 1885-08-12
HUMAN REMIiNS IN XEXTC0
LErrxR FROM PROFESSOR MEwpuRwY

70 fAs Edttor OF TAs TrsSvws.
SIR: have read with much interest II
article by Senior Barcena in the August number Of ~
Natxrai the discovery Of some human remains -
the City Of Mexico, also the letter signed sB" -
your comments In roccnt Issues Of TIE TRIBUNE,
While recognizing the importance Of this dscovsey -
giving promise Of something positive in regard =
the early history Of man this continent an osn.
PEELED to say that the facts reported BY Senior Baroaa
have In themselves very little geological or archo>-
logical Significance Tho bones found IN frsvert,na
q subaeral and not sub squeous formation. depositsa
in the waters Of the lake, has been inferred buh
from lime spring, and perhaps at the level Il nv
occupies The carbonate Of lime II dissolved By an
water that has carbenic acid In solution and t prsep-
tated In the form Of travcrne ca,careous tua whoa
that water is evaporated and most persons have sesa
local accumulaons Of this material incrustug sasea
twigs land Shells etc. In q water basin the lime 4 MOI
preciptafed unless withdrawn-as It may be even ron
q weak s0utlon-by mollusks foramnifers, to form
their shells, until the solution becomes saturated Thea
coating OF lims the bottom and incru,ts ell
objects that lie in the water Such preciptate hes
been formed by the drying away OF lakes Neyada and
in the Colorado desert; but there aud in oil such cases
the precipitate Is general, rises to uniform height eli
about the basin. and is permanent and unnistakabs
record No such precipitate has lined the sides snA
bottom Of Lake Tezcoco and It Is evident therefore, that
this is local deposit made by spring.
is true Senior Barcens states. that the tua OF
travertine contains much silica this would he evidence
that the water from which 1t was deposited was hot
since hot water especially when aIkaiies prcsert Il
powerful solvent of silica. while cold water has almost
effect upon IT, Carbonaet hot watcr is also much
powerful solvent OF lime than cold water and the
almost mountainous Of this material deposited
at the MamHOth Hot Springs. Yellowstone Park, show
what q load OF lime hot water can carry Tho geyscrs
OF the Park are surrounded by great accumuatops OF
silica because the rocks cached these bot springs
rhyoes that highly sciols and contain little lime.
The Mammoth Hot Springs nndoubtsdy fow through tie
great of limestone which lies at the north end of the
Park. Where rocks OF both kinds leached by hot
water, silica and lime may be deposited together and
sucn supp Is the case In the locality where the
bones found.
From this 1t will be seen that the deposit has no geo
logical position or age, and tiat II Is altogether
superficial accumulation that. judging from tie facts
reported. affords proof OF exteme antiquity. wre
this not in depreciation OF the interesting discovery OF
scnOr Barcena. but to prevent msapprebenson and
encourage further search In the locality thar has yielded
these fossils for others that may enable TO do what
these do not fix an age to the deposits t possible
have In these bones tue oil lest record Of name
occupation OF the continent but facts have yet bean
brought to light which prove that the DEPOSIT containing
them not made within thousand years
Columbia college, Aug 10. 1855. J. s. NEwBfRRr.