Polk County news-gazette. (Benton, Tenn.) 190?-191?, 1914-07-30

The maximum tides in these pipes did not ex-
coed onethousandth of an inch; but so perfect
was the apparatus and so accurate the readings
by Professor Nicholson that all the variations IN
the tides we're accurately determined rides are
complex things Their height varies with the
position and distance Of both the sun and the
moon and therefore, is never the same two days
in succession.
Professor Michelson's experiments revealed 80
of these variations which correspondent almost
exactly with the variations obtained theoretically
by computing the variations in the attractive
forces exerted by the sun and the moon inc
practical correspondence of the actual height OF
the tides with the theoretical height proved that
the earth through and through is as rigid as steel
and that it yields to outside forces as perfectly
elastic body and not as viscous mass
This experiment reveals the Imagination ana
the striking originality of Professor M1chelson.
The first achievement to bring his name to the
attention of the scientific world was his accurate
determination OF the velocity of light accom-
plished also after overcoming tremendous expert
mental difficulties. Light is the fastest thing In
nature ii represents the absolute limit OF speed
After four years of work and study, Professor
Nicholson announced that light travels with
velocity OF $500 miles per second Thes maxi
mum error In this figure does not exceed one
fortieth OF per cent
On the subject of spectrum analysis Professor
Nicholson has devoted many of the best years OF
his life Spectrum analyses are obtained Dy
means OF the spectroscope. Every substance
when heated emits Characteristic light by
means of the spectroscope this light Is analysed
and the elements giving of the light are thereoy
revealed The spectroscope has enabled SCI
entists to determine the elements In rar distant
stars. II has made possible tremendously impor-
tant discoveries concerning the nature OF atoms
the minute particles of which all matter Is com
posed.
The difficulties of spectrum analysis will be
realized when II is learned that single atom OF
sodium emits 100000 100000 vibrations per Sec
ond OF two slightly different kinds OF lght FRO
fessor Nicholson was engaged In spectrum
analysis very long before he improved the spec
troscope calling the improved type an echelon
spectroscope This wonderful machine divides
light into its various constituents and makes pos
sible their separate analysis
The echelon spectroscope uses glass grating
"a piece of highly polished glass on which Is
ruled from $4,000 to $4,000 straight equally-spaced
lessor Nicholson invented ruling engine that Is
the most accurately constructed mechanical de'
vice in the world II is operated in room the
temperature Of which is kept constant to within
onehundredth of a degree.
TO assist in analysing the lines Of the spectrum
into their fundamental constituents, Professor
Nicholson invented the harmonic analyzer
machine as complicated and delicate as the
linotype machine BY Its use an assistant can III
a few minutes make calculations that would take
a skilled computer weeks to accomplish.
Scientists have long endeavored to determine
the absolute motion of the earth through space
II Is known that the earth swings around the sun