The Indiana State sentinel. [volume] (Indianapolis) 1868-1895, 1878-07-03
SCIENTIFIC WONDERS.
Professor Edison Explains His Latest
Dfscoverfes-The Tasfmeter and EIec-
trio Governor-How the Secrets of the
Sum Are to be Ferrefed Ont.

Dfscoverfes-The Tasfmeter ana Elec-
trio Governor-How the Secrets of the
Sum Are to be Ferreted Out.
New York Herald.l
The latest marvel from Menlo park is the
"tasimeter," or instrument for the measure
ment of pressure, which Professor Edison
has just completed. 1t is to be. used in
the scientific experiments to be made by as
tronomers from all parts of the world at
Denver Colorado, next month, during the
total eclipse of the sun, visible at that place
Professor Edison starts for that state on the
Sth of July, accompanied by Professor Ora
per- Barker and other scientists from this
section of the country. The results thus far
obtained from the tasimeter have been al.
most incredible. Used in connection with
the galvanometer of Sir William Thompson,
1T has been found 10 record the pressure Of
one five hundredth thousandth part of an
inch.
Hitherto the most delicate instrument
known to science for determining the heat
in the different parts of the soar spectrum
has been the thermopile. The great improve
ment of the tssimeter over the tbermopile is
illustrated in simple manner by Professor
Edison. \ few inches from the former he
placed hot iron. 1t defec:ed the needle OF
an ordinary galvanometer one degree; then
he held his little finger four inches from the
tasimeter with the same galvanometer, and
it swung the needle around six degrees. In
explaining the workings of his new inven-
ton to a Herald reporter, in his laboratory
at MenlO park yesterday, the inventor said:
I'VE now study chemistry by means of the
sun. We have found by the aid of the spec
troscope that there are metals in the sun
which are unknown on earth, as we'll as
metals here the existence of which in the
sun have thus far not been discovered"
CURIOUS EXPERIMENTS.
The professor then made a number of Gu
rious experiments. 'See here" said he,
taking up thin strip of vulcanized rubber
and placing it between two small upright
iron posts in his tasimeter; this is highly
sensitive to heat-a little causes it to ex-
pand. At this end | place carbon. | found
out that silk coated with conducting lamp
black, pressed in the form of button, was
wonderfully sensitive to the passage of cleo
trio current. Put upon it the pressure of
one-half millionth of an inch aud it will
allow the passage of a current strong enough
to defect Sir William Thompson's galvan-
ometer one degree. OF course greater pres
sure defects the needle more" Professor
Edison then took an ordinary galvanOmeter
and put it in electricity circuit with his
tasimeter and held his hand tour inches
away from the vulcanite strip. Instantly
the needle of the galvanOmeter moved five
degrees. Next he lighted gas Jet five fs ct
away, and the needle moved four degrees.
Then he held match distance of six inches
and the heat indicated IL degrees in the gal
Yanometer. Breathing slightly on the rub
Der expanded it sufficiently to mark 30 de-
grees. These results the professor produced
without the improved galvanometer, which
he explained was infinitely more sensitive.
MEASURING MOISTURE.
Professor Edison next introduced between
the posts slip of gelatlne, in order to meas
ure moisture. Moistening piece of paper
slightly with his tongue he held it three
inches away. The detection was eight de-
grees. A breath on the gelatine moved the
pointer thirty-fve degrees. A drop of water
on the end of his finger, held five inches
away, indicated a moisture of eleven de-
grees A lighted cigar, at distance of nearly
a foot. dried the atmosphere sufficiently to
cause detection of seven degrees. Water
in bottle held near by made the needle
vibrate
THE ECLIPSE OF THE sun.
The professor next explained the method
proposed to be adopted in the Astronomical
experiments to be made with his tasimster
Instead of vulcanized rubber, platina will bt
used. the latter having been found 70 gair
and lose heat much more readily than tn,
/ former. The taslmeter, unlike the one ex
/ penmented upon as above, is to be smaller
/ and of different material, brass being used
/ throughout. 1t will be inclosed in a recep
/ tacle of tin, which in turn is placed In a sec
/ ond rece ptacle of the same metal. Between
the two will be kept boiling water for the
! purpose of preserving evenness of tempera
/ ture. as boiling water attains no higher tenn
pera;ure than 2l2 degrees Fahrenheit The
/ spectrJscope will then be made to concen
trate the heat into small opening in the
tssimeter, where, falling on the platina, il
will cause expansion AID corresponding
pressure of the small carbon button, allow
ing the passage of the electric current in
degree commensurate with the pressure
Attached to and forming part of the tasime
/ ter is an appliance for measuring the degret
/ of expansion or contraction of different met
ais under similar temperatures. ProfessO
Edison found the heat of his hand expanded
the platina one FIVE thoussndth part of al
inch.
ICEBERGs MADE HARMLESS.
The great inventor has already taken step
to use his new discovery for the protection
of vessels at sea. He stated TO the write
his method as follows: II arrange the carbon
button a highly sensitive barometer, and
| inclosing it in a case, connect it with thu
keel OF ship. then run wire to the cap
tain's room into 81 ordinary galvanometer
Any change of temperature, as you see is a.
once indicated Goodness of the water will
contract and warmth expand and the CORE
spending reflections be placed at once befor'
the eye of the captain. The approach of al
iceberg WILL therefore, be known long befor'
there is danger of collision. 1t may also b,
used to indicate any abnormal heat in an.
part of the ships hold, thus giving timely
notice OF the breaking out OF fire"
DISCOVERY IN TELEGRAPHY.
In experimenting on his tasimeter, Profes
sor Edison made highly valuable discovery
in telegraphy. Ever since the first line was
successfully worked by Professor Morse To,
great and apparently iDsurmountable oh
stacle to constant and uninterrupted com
munication was the effect produced on tn,
electric current by changes in the atmos
pDere. Rain always made the lines worl
with difficulty, and frequently in heav,
storms the escape of the subtle fluid tn,
moist air made the wires practically useless
The professors discovery is what he call
an electric governor" ling on the tele
| graph line as a steam governor does on al
engine. 1t obviates the necessity of adjust
| ing the magnet armatuTes along the line
! One placed in the circuit regulates the en-
tire line, preserving the evenness of current
throughout. The loss of 30 per cent of the
battery power is felt no more than a CORES