The daily Gate City. [volume] (Keokuk, Iowa) 1855-1916, 1856-01-03

Xhcrln NInelPrA.

ths rim OmeEFFs-
MEssRs. EplroRs The method of testing
these instruments is given with sufficient full
ness, in Turner's Chemistry, page %, Am.
Ed, bv Prof Backe. But for the use Of
those not accustomed to performing expert
ments with glass, the same directions IN sub
stance. may be more safely presented in an
other way.
Take cast iron stove boiler, which will
hold about three gallons, and one which is
largest at the top,--and put into this pure
rain or snow water, to the depth Of one inch,
not less, nor much over. Draw the plate on
which the bulb and tube are fastened, out of
its case, lash the top Of this plate to piece
of board at least one inch square, and long
enough to reach across the boiler. If grooves
or notches are cut in this board, SO as to Let
it down on the sides of the boiler half an
lnch so much the better. Attach the plate
to this stick in such a way as just to let the
bulb into the water deep enough to be COW
cred, yet not so deep Is that either the bulb
or the plate shall reach the bottom of the
kettle. Place no cover upon the boiler, but
let the steam rise up and envelope the stem
of the bulb, 1t will be safest to put cold
water into the boiler, and have the bulb adj
justed before heating. The bulb plate must
be made so fast that the boiling of the water
will not disturb it, or the tube may be bro
ken. When ali is ready, place the boiler on
the stove and bring the water to a smart boil.
But Let the windows and doors be kept shut,
the while, so that the steam may rise straight
up. The temperature of the room must be
fully Us warm as il comfortable If one has
a barometer, this should stand at 80 inches.
But without this, the above temperature will
answer.
When the water bubbles all over the bot
tom Of the boiler, the mercury must stand
still ut 2l2 deg. above zero. II ii does so,
the thermometer is right at that point.
The freezing point is found by burying the
tube in pounded ice, where it is warm enough
to slowlv,,melt the ice; and letting it remain
in this condition till the mercury becomes
stationary. That is the freezing point
Between this and the point of boiling there
must be $50 deg. accurately marked. just
the distance of 81 deg. Of these degrees be-
lom the freezing point is zcro,- making the
boiling point PIP deg. above zero.
/ But the freezing point need not be tested
provided indications Of freezing can be seen
when the mercury stands at 81 deg. above
i zero. Take n nice pair Of diriders, such rs are
used for drawing, and ascertain whether the
| degree marks below the freezing point cor
respond, in distance from each other, with
those above that point. If so, all we'll
/ All thermometers which have the zero,
! freezing, and boiling points correctly made.
/ with well marked scale. will give the same
| temperature in the same circumstances.
These directions have been drawn out al
/ length, not for the benefit Of practiced OK
/ perimenters, but for those who are not
I There is not the least danger Of breaking the
thcrmometcr III tuIs TrlaI, pruv1ucu TT
handled carefully.
But If those possessed Of such nm instru-
ment will subject it to this test, we predict
that in more than half the eases, they will
make discovery. II. 4.