The Washington herald., 1908-01-19

New York, Jan. ls-If Koresh. the as
tronomer-wh0 startled the world a few
years ago by announcing that the earth
/ is concave, and that we are living inside
a sphere instead of outside-wiH come up
10 Columbia University on Friday. Feb
ruary Z, or Wednesday, February y. he
viii get hrst-hand proof that the earth
is round, and that il revoIfes around the
sun. On these two days. Prof. Harold
Jacoby, head of the department Of as
trOnomy at Columbia and his assistant
Or. 5. A Mitchell, viii reopen the famous
experiment of Foucault. the most inge-
NOUS Of French physicists who in 1851
gave the first actual evidence Of the
earth's rotary movement
Most people" said Dr. Mitchell In ex-
planning the experiment. know that the
earth moves around the sun instead of
the sun moving around the earth. But If
you ask ninety-nine persons out Of a
hundred why this is So they will be un-
able to answer. To any one seeing the
sun rise in the east. move through the
heavens and disappear in the west. It
would appear as plausible. with that phe-
nomenon alone as a guide. 10 believe that
the sun moves. as TO believe that the
earth does. In fact, you cannot make
children or aborigines believe otherwise.
VIII Use New Chapel.
In order that people may see actual
Of
we are going to repeat the experiment
devised and performed by FoucauIt more
than fifty years ago We will take St
Paul's chapel built for the university last
year, and suspend from its cupola. on a
wire 81 feet long. a 150-pound unloaded
shell. so that it is but few inches above
the floor
This is held out OF vertical by a loose
band. which is fixed by piece Of string
ten feet TO one side of equilibrium After
the ball has been kept in position for an
hour. so that everythlng-ev the wire
viii be absolutely wIJ.CCt any disturbing
vibration. match is touched 10 the
string, This burning. releases the loose
band. which. dropping, lets the ball swing
back and forth like a pendulum, in a
straight line over a previously ruled
straight line on the floor
Attached 10 the bottom OF the ball is
a brush wet with ink AT each swing
this marks a circular piece OF paper
placed beneath il. Although the pen
dulum makes a straight line at each
swing. II VIII be observed that each line
is farther 70 the right and that no line
crosses another except in the center of
1.-THE position Of the ball II al rest.
IN the thirty-six hours this line. II the
pendulum could be kept swinging, would
form the radH of an entire circle. At the
north pole. where the rotation OF the
earth is faster, it would take only twenty
four hours.
Building Turns Around Bail.
The reason for the phenomenon is that
| the bali is suspended in space and the
/ building and the paper on its floor are
/ fixed in a definite spot on the earth. The
/ building twists around with the revolu-
| tion of the earth while the ball always
swings in the same position. In time the
| floor makes a complete circle around the
pendulum.
| 'FOacault performed the experiment for
| the first time at the Pantheon in Paris.
with a pendulum 200 feet long. But we
/ hope TO get as good results with 81 feet"
! Prof. Jacoby when asked whether he
/ had undertaken the experiment to silence
| astronomers having absurd theories about
/ the eartl1's revolution. replied
| No, We don't try particularly 10 refute
| the theories Of any crank We don't even
| expect TO establish any new law or record
I any new observation. We merely want to
| demonstrate TO the university and TO the
public the proof Of a well-knoWn prin-
Cipie.
| The experiment has not been tried in
/ this country for years. Up here at Co
lumbia we had been handicapped hereto
/ fore by not having any building with a
| roof high enough. But with the erection
OF the new chapel this difficulty has been
met. and there is no reason why we
should not again demonstrate the reli-
ability Of Foucault's evidence"