The Indianapolis times. [volume] (Indianapolis [Ind.]) 1922-1965, 1933-10-20
-Dietz on Science
BRASS BRAIN
is TRIUMPH OF
MACHINE ACE
Intricate Problems Solved
for Scientists by
Invention.
BY DAVID DIETZ
Scripps Howard Science Editor

BY DAVID DIETZ
Scripps- Howard Science Editor
The 'periodometer" is a triumph
of the machine age. The machine
is the invention of DR.. c. G.. Abbot.
secretary Of the Smithsonian Insti-
tuition.
1t is machine for solving IN
tricate mathematical problems and
because it seems to the onlooker
as though it almost was capable Of
/ thinking, it has been nicknamed the
braSS-brain."
Mathematical machines have been
among the most interesting de-
velopments of the machine age.
Every one, of course, Is familiar
with the ordinary adding machine.
However, there are more intricate
calculating machines which multiply
and divide as well, furnish squares
or square roots, and so on.
These machines have come into
widespread use in banks, insurance
companies and many business Or
CARNATIONS, as we'll as in scientific
laboratories and astronomical OBJ
servatories. They are particularly
valuable to engineers and architects.
Predicted Tide Hour
More interesting, though of more
specialized uses, are the still more
intricate machines. A number of
these deal with periodical phe-
nomena where the result sought is
the total effect OF a number of fac
tors. All the factors are operating
regularly or periodically but with
different time periods. The total
effect, therefore, itself is an involved
cycle.
One of the early mathematical
machines was a tide predictor, sug-
gested by Lord Kelvin in 1876 at
a meeting of the British Association
for the Advancement of Science.
The tide in any particular harbor
varies from day to day as a result
of many factors, among them, Of
course, the position of the moon.
Lord Kelvin suggested machine
consisting of eccentric wheels which
could be set to represent variety
of factors.
Chain Operates Pointer
The motions of all these wheels
were communicated to chain
which in turn operated a pointer.
1t was possible, therefore, to set the
wheels to represent the factors for
any harbor. The machine then
would predict the tide at any future
date. Lord Kelvin's machine now is
in the South Kensington museum
But machines based on its principle
are in use all over the world. The
United States coast and geodeti0
survey has one in Washington.
DR.. Dayton c. Miller, former
president of the American Physical
| society, has two mathematical ma
chimes for the study of sound waves,
These are the most thorough ma
chimes of their kind in existence.
A sound wave is a complex vibrav
ton of the air DR.. Miller invented
machine known as the phonedeik
which turns sound waves into move-
ments Of beam of light and makes
it possible to photograph them. The
| mathematical machines are for
studying the complex curves to
which the phonedeik reduces a
sound wave.
One Draws Curves
One machine, known as the Hens
rici analyzer, will separate a CONF
pick curve into its component parts
and indicate on dials the mathe-
NAUTICAL equation representing those
curves.
The other, known as the synthe-
sizer, does the opposite trick. If its
wheels are set according to the
mathematical equation, it auto
matically draws the curves which
| they represent.
DR.. Abbot's machine attacks a
problem somewhat similar to that
of the tide predictor or the sound
wave machines. But in some ways
it is still more difficult machine.
DR.. Abbot's periodometer is a sorH
Of mechanical Sherlock Holmes His
chief interest for many years has
been the study of the sun and in
particular the effect of solar radia-
ton upon the weather. He has been
the foremost figure in this work, in
venting a number of instruments
for studying the suns radiation,
Suns Radiation Varies
Under DR.. Abbot's direction. the
Smithsonian Institution has estabs
lished observatories on high moun~
tains in widely scattered locaitiea
to study the sun.
Dr. Abbot believes that the suns
radiation varies from day to day
and that these variations are the
primary cause of variations in the
weather.
Now, in studying weather from
day to day, DR.. Abbot was interested
in finding whether or not there vera
underlying factors which went in
cycles or periods. If such cycls
can be found, then the task Of find~
ing its cause is considerably simple
fed.
And that is the purpose Of the
periodometer - TO take a complies
curve, such as the daily fluctuations
represent, and attempt to find the
underlying cycles or periods in it.