Evening star. [volume] (Washington, D.C.) 1854-1972, 1898-10-01
Interesting Experiments Which May
Solve an Old Problem.
ITS CENTER FIRE is COOLING OFF
Curious Apparatus to Measure
Heat and Cold.
CON CTIVITY OF ROCK
Special Correspondence Of The Evening Star.

| Special Correspondence of The Evening Star.
| CAMBRIDGE, Mass. September IS 1898.
| In the geological laboratory of Harvard
University an interesting series of expert
| ments is being carried on to determine the
| age of the earth. The question is an old
| one. and many guesses of more OF less sci
entific eXactness have ben made in the PAST
endeavCrs to solve 1t. These have been bas-
] ed for the most part on the situation and
formation of rock and earth deposits the
decay of vegetable matter Prof. b. o.
| Pierce ard r. W, Wilson, who are carry
| ing on the present tests, are working by d
| new process. which involves the use OF
| mechanism for testing the conductivity of
different grades of rock taken from differ
ent places. including the deepest hole that
| has ever been sunk into the earth. Incident
ally the process also involves interesting
| mining problems namely. the getting Of
gold from very deep levels and other ques-
| IONS of deep Shafting. 1t will proha bly, set
tie the question of why certain parts of the
| interior of the earth are hotter or colder
than other parts, laying down rules of sci
entffic accuracy.
| The Investigations are being carried on
under the auspices Of the Rumford fund
ard the professors who are conducting lem
| are being supplied with material for the
search by Prof. Alexander Agassz Prof.
Aeassiz is chief owner of the Calumet
| and Hecla mine the deepest in the world.
| The upper levels Of this mine have been
worked out. but as the shafts have been
| driven deeper and deeper the ore continues
| as plentiful AS ever. Immense fortunes
have been taken out of this great hole. and
| 1t is of value to scientists because the shaft.
being now nearly mile deep. bas permit
| ted examination of the interior of the earth
| such as has not been had before. 1t has
been agreed among scientists generally
| that raging fires no longer exist in the in
| terror of the earth. They believe that the
center of the earth is very hot bur that
this latent heat is what remains of the cool
! ing process which has been going on for
millions OF years. Like a fallen cannon
ball, the earth is cooling off from the sur
| face toward the center. but the general
pressure all sides prevents the confa-
grafton from raging within. According to
this hypothesis the temperature ought to
increase gradually but surely the earth
is penetrated. This has proved 70 be the
case in every deep hole which has been dug
in the earth except in the Calumet and
Hecla mine.
In we'll which is over 5000 feet deep
! near Pittsburg. Pa, Prof. Haliock OF CO.
| lumbia College found that the Temperature
rose one degree tor every fifty feet the
Thermometer was lowered. Al 5su feet
the temperature was found to be 1919 de-
grees FIJI At $500 the temperature was
12S degrees. In another deep well near
Wheeling Pa. the temperature at 1870
feet is TO degrees In the SpererberE salt
WI Resr Berlin. Gef many. the temporary
at 4,110 feet is 10 degrees. The Schalada-
bach salt well near Leipsic has tempera-
ture Of 1853 degrees at $40 feet. Yet
these temperatures are surpassed. as far
as rapid rise is concerned. in holes bored
in Eeyser regions. In the Sutro tunnel,
which does not go far beneath the surface,
tie heat is so intense that the men en-
rlcyed therein are compelled to work in
twenty-minute shifts.
Exception to the Rule.
Now, all this is directly in eentradistiHc-
ton to what has been found TO exist in ;he
Calumet and Hecia mine. At depth OF a
mile the labcrers work all day in tenn
perature Of 10 deg ees. which condition. 1t
must be added. is not brought about by any
elaborate system Of ventilation. Seventy
degrees is the natural temperature at the
bottom of the mine. Prof. Agassiz has
made come elaborate experiments in testing
the general temperature Of the nine. He
caused to be paced. at regular depths a
Eumber OF thermometers. He had them
walled up the inches III the rock and left
them there months at time. These ther-
mometsrs were se1-re2istering. That is.
the mercury would ascend to the point OF
| the highest temperature which acted upon
them during their stay in the rock but
crook In the mercury tube prevented the
mercury from ever descending. II could
always rise bat II could never run back.
SO II was compelled to stay - the point OF
greatest temperature. When Prof Asas-z
uuearthsd his instruments. however, he
1CUlO q ET6at unllofhlty III the kttici~A
temperature of his mine. Evidently he
gradual rise in temperature ala not hold IN
the Lake Superior district in which the
mine is located as ii did elsewhere.
The questions now arose: ny was this
>o?' did IL not have a strong bearing on
the manner in when the earth cooled dur
ing geological ages Gould not the con-
dition be cxnerimentcd upon and the re-
| suits be utilized in some economic man.
ner?'' Clearly the condition surrounding
! the copper mines in Michigan was th-a re-
suit Of the very bow oonductivity of the
surrounding rock. Evidently thls rock had
not the power of conducting heat a..d cola
to the degree manifested by rock in either
parts of the earth. The internal hent of
the earth does not rise IN through IL
easily. for instance. as II does in the rock
surrounding the well upon which Professor
Haliock exnerTlentsd near Pittshurg Ia.
Just what is the difference. how ever, Is not
SO easy 10 determine ard This really is what
Professors Pierce and Wilson of Harvard
are trying to find out. When they have
done so they will have established bass
of ejaculation from which some new f;scts
may be CLEANED and uI,on which some
startling theories may be built.
Experiments With Rock
The apparatus In use in !ts way is as
curious as the Information il is intended to
discover. AS it stands ii is a growth, as
various forms were tried before this one
was produced The exnerimcntors first
procured several slabs of rock from the
very bottom OF the Calumet and Hecla
| mine. Their idea was 10 cool siab on one
side to the freezing point; to heat il on the
other sil at the same time To the aoilins
point-that is 10 say, TO the temperature of
live steam-and then ty electrical means TO
measure the SLOW passage of neat and cold
to. ard from the middle or interior Of the
slab. Several slabs are placed In the APP
paratus at once. They are olA-rDed be-
tween two platforms Of cast iron. The
upper platform holds up deep tray which
is filled with $50 pounds OF Ice; the lower