Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1884-01-04
How the Mercury 10 Got Into The
Tube-Extent of the Defects I'm In
strun,en4s

boiling water and the point to which
the mercury rises is marked ON the
scale as PIP degrees. Ten degrees of
the mercury are now detached from
the column by iarring, and the whole
length of the tuue is tested. The pro
cess is repeated with five degrees of
the column, being measured all the
time by standard Thermometer to
see if the tube is conicai at any
point"
Are common thermometers usually
correct?"
They generally vary about two or
three degrees, owing to the irregulari-
ty of the opening in the tube, which
causes the mercury to rise slowly
where the opening is too large and
too fast where the opening is too mar
row. 1t requires great skill to blow a
tube with uniform opening the
whole length"
Are Thermometers ready for use
Immediately after they are filled with
mercury2"
They should be allowed to stand
no less than one month-one year is
better-to allow the mercury TO set
tie before the scale is made"
What are the different kinds that
are made.
This self registering thermometer
is used for marking the highest and
lowest peints reached within given
time The bulb is filled with mercu-
ry, above which, in the tube, is inser-
ted a fine piece of steel spring; the
remainder of the tube is filled with
carbolic acid or creosote. The steel
spring rests at the highest point and
is pushed to by the mercury and is af-
terward drawn down by a small mag
net. By duplex arrangement and
revising the scale the lowest or cold
est point is indicated in the same
way. The deepsea thermometer is of
the sRpAeIpattern, and is encased in a
henvvscc Dners tubeato preserve it from
the prsssafe 95 VA wst.s sr s 4 q has besides,
q self regulating attachment. adEhe
fever rAclinicaE thefnfo ofneteiS ate
made with great nicely, aud are used
for determining the Temperatures Of
the human body.
What are used for filling bulbs of
thermometers! 2"
Mercury is commonly used. it be-
- s highly snns;tis . to hcG.t and cold,
but for the extreme northern climates
it will not answer, as it freezes at
40 degrees below zero. Where this
temperature is liable to be met, spirit
thermometers are used, being made
of alchohol colored red and blue
These spirit thermometers will not
answer for high Temperatures how
ever, rs the alchohol volatililes too
readily"
rs there a government standard for
testing thermometers?"
There is no government standard
The signal service uses the Fahren-
heit scale The Winchester observa-
tory of Yale college has established a
thermometrio bureau for testing ther-
mometers either for dealers or other
interested in procuring exact instru-
ments A small fee. ranging from so
cents to 81, is charged, and Yale GER
tificate of correctness is furnished
The observatory has elaborate appar-
atus for testing thermometers and its
services are of great value to physl-
clans III testing clinical thermometers.
The observatory has issued circular
to physicians which contains the fol
lowing statements: The competition
of business, coupled with the entire
absence up to this time of any large
observatory in this country paying
special attention to thermometry, &c
which authoritative appeal could be
made, has SO affected the manufacture
ers of thermometers for medical
purposes, that it seems necessary to
issue a card briefly indicating the
errors commonly found to exist, and
explain why in this case the representa-,
ton of the dealers may be at fault
through the want of proper under,
standing of the subtle errors to which
medical thermometers are liable Toe
great desire to economic time, good
material, and skilled labor has led, in
in the making of thermometers to the
| following faults: ~ The graduation
is sometimes started from one point OF
the scale, near the normal, and the
size of the capillary tube is guessed at
No upper point being fixed by the
maker, the higher graduates may be
erroneous to the extent of several de
grees. ~ Too much air separating
the index from the column OF mer
curry causes the index to rise with a
ierky motion; air above the index
forces the index down when the ther.
mometer is taken away from thu
body. In thermometers errors from
this cause amout to degrees at high
temperature ~ New thermometers
increase their readings rapidly during
the first months after manufacture, sc
that instruments which were right
when made, may change their indica
tions as much as 2 degrees within a
year"
Are there any late improvements
in thermometers2
In the old style of clinical ther.
mometer there was a small space oi
oxygeniZed air separating the column
of mercury that held the upper por-
ton of mercury at the maximum
po;.it; now contraction is made in
the tube that retains the mercury al
the maximum point, until it is Jared
back to its place. There is also new
style of PLAIN thermometer made with
an elongated bulb. with the tube bal
anced near the center on a pivot As
the mercury rises above the pivot the
point is depressed, and moves along
an index, ike the hand of a clock.
This Thermometer can be read with
ease across large hall. There are
also many new contrivances for reg.
isterins degrees of heat and cold, with
clock attachments TO indicate the hour
the temperature indicated was reached.
Thermometers are also made with
wire attachments, 50 that the mercury
rising to certain point viii touch the
wire and complete the circuit of gal.
vanic battery and sound an alarm.
These are Useful IN the drying-rooms
OF paper manufactures, in green
houses. and as provision against ac-
ciden tai fire
Cheating al Poker.
Washington Letter IN Chicago yeEs.