The Nezperce herald. (Nezperce, Idaho) 1900-1957, 1904-06-09
THERMOMETER MAkINo
now Boiling and Pressing Points Al
Fous and Degrees Marked.


Now Boiling aud Frsesins Points An
FousA and Degrees Marked.
The making Of a thermometer MAY
be eithes delicate scientific operation
or ono OF the simplest tasks OF the
skilled mechanic. according 10 the son
Of Thermometer made. With the ex,
tremely sensitive and minuteIy aecur-
ate instruments designed for scientific
uses great care is taken and they are
Kept In stock for months. sometimes
years. 10 be compared with instru-
nients that are known 10 be trust
worthy. But 80 much time cannot be
spent over the comparatively cheap
thermometer In common use. and these
are made rapidly. though always care
fully.
Mercury is generally used for scien'
the Instruments. but most makers pre-
fer alcohol because IL is cheaper. The
alcohol Is coiored red with aDiline dye.
which does not fade. The tbermom-
ster maker buys his glass tubes In
long strips from the glass factories.
The glass blower on the premises cuts
these tubes 10 the proper lengths. and
with his gas JET and blowpipe makes
The bulb on the lower end. The bulb
are then flled with colored alcohol ano
the tubes stand for rwenty-four hours
On the following day another workman
holds each bulb Ia turn over a gas jet
uniii the coiored fiuid by its expansion
entirely nils the tube. IL then goes
back into the hands OF the glass blow.
er. He closes, the upper snd and turns
the tip backward 10 make little hook
which viii help keep the tube In place
In the frame.
The tubes rest until some hundreds
OF them. perhaps thousands. are ready. I
Then the process OF gauging begins
There are no marks on the tube and
the nrst guide-mark TO be made is the
freezing point 81 degrees Fahrenheit
Ihis 10 found by plunging the bulb
Into melting snow. No other thermom-
eter Is needed for a guide. for melting
snow gives invariably the exact freez.
ING point This 10 an unfailing test for
any thermometer when accuracy may
be suspected But melting snow ID
not always 10 be had and a little ma.
chine resembling a sausage grinder Ia
brought into use. This machine shaves
block OF Ice into particles. which
answer the purpose as well as snow. ,
When the bulbs have been long enough
"a The melting snow a workman takes ,
hem one by one from their bath. seiE. ,
ng each ~ that his thumb nail marks
he exact spot 10 which the nuid has
allen Here be makes a scarcely per /,
'~puhle mark upon the glass with !
me nie. and goes on TO the next
The tubes. with the freezing point
aAFked on each. now so into the hands +,
Z another workman. who plunges the :,
'uib into vessel allied with water
opt constantly AZ 50 degrees This =
} marked Ike the Others. and the tube
now supplied with these guide :,
isrks. each 81 degrees from the next
With its Individuality thus establish .,
.. the tuba goes into the hands OF
iafker. who CTS It's bulb and hook :.
TO The frame Il Is 10 occupy and
,akcs slight scratches on the frame
lrrcSponding 10 the 81 degrees. O. >,
cgnees and 90 degrees marks on the =
lie. !,
The frame. whether II be wood. tin !,
brass. goes 10 the gsnging room. :,
here u Is laid upon a s,eepiy sioping s,
BILE marked exactly In the position =,
e Thermometer OF that size.
A long. straight bar OF wood or met. q,
extends diaxonaily across the table =,
ON The lower right-hsss corner 10 =,
g upper iefi-hsnd conner. ON tho :.
,hi this rrss upon psvoi and on
Q left u rests In q rachel. which lets
ascend OF descend only one notch
a time. Each notch marks the er.
distance Of two degrees. London
press !