Coeur d'Alene evening press. (Coeur d'Alene, Idaho) 1907-1929, 1909-09-21
THE COLI sALL.
How Gravity is Fooled In Its Flight
Through the Air.

How Gravity Is Fooled In lts Flight
Through the Air.
Professor Petrie Guthrie TAFT had lit.
tie skill at golf but vast deal at sci
ence Among the many problems to
which he applied his genius were some
concerning that apparently simple
thing. the flight Of a golf ball And
here he found difficulties so battling
that. though he worked over them for
years and called on other scientists for
assistance, many mysteries still re-
NAMED One question that he solved.
however. Is OF curious interest.
The force of gravity is the one force
we know us most constant and inevlta-
BILE. To defeat gravity is almost to
suspend one Of natures laws In bis
investigations Professor TAFT suddenly
became aware that gravity was de-
feated by the golf ball. The fact ad-
mltted no doubt. On timing the flight
OF the ball he discovered that II re-
manned in the air almost twice as long
as 1t should have under the influence of
gravity. Thus. with gravity acting as
usual on other things, a drive of 200
yards would be completed in three
and half seconds A thrown bali,
for example, describing the same ira
jectory, would remain In the air only
that length of time. The golf ball in
passing over that 200 yards hoated Sc
renely through the air for six and a
half seconds
1t was clear, then. that In some man.
ner the gravity was thwarted, Pro
fessor TAFT attacked the problem of
the means. and In the end he solved It.
After searching long he found the
cause Of the prolonged flight in the 70
tatlon given to the ball by the clubs
impact. The secret lay in the manner
Of the stroke from the tee.
The first principle OF the explanation
Is in the simple fact that an Object
poised In the air has an equal atmos
pheric pressure on 1t at all points. The
second principle is that when sphere
rotates In a current OF air the side o.
the sphere which Is advancing to NEE
the current Is subjected to create
pressure than Is that side which 1
moving In the direction OF the current
To illustrate. when the golfer slices hi
ball II Is made to spin In such fashion
that Its front side Is constantly II
movement to the right. Therefore th,
pressure OF the air Is greater on tn,
left side than on the right. and the bal
curves to the right When the ball 1
pulled. the operation Is reversed. AM
the flight bends away to the left. So |
the ball Is topped the spinning dlreC
ton OF the front is downward. Thus th
pull OF gravity is aided and the tilgh
Is swiftly checked. But every properl
driven ball receives an undercut B
the underspln thus impaired the from
side OF the ball Is made to spin ~
ward; the added pressure Is from bs
low and Is In consequence directly OF
posed 10 gravity. The result IL a iiIgh
sustained. but little less than twice a
long as Il would be without this under
spin Moreover, Professor TAFT demon
strated that without this undercu
when driving the ball would trav,
only about half It's usual distance.
The ordinary golfer IL quite unawaE
that he gives any undeFspln TO his be.
drives, but be does. Without the u
dercut his driving would be a eontinI
Gus failure Chicago Record Heral1