The Princeton union. [volume] (Princeton, Minn.) 1876-1976, 1891-09-10
another, which illustrates to us the
force known ais cohesion. 5

/ 4 z
moves readily in the water the cause
OF 1t is the well-known property Of
camphor to agltate itself on the sur
lace OF Water, as a small piece of cam
phOr placed in a tumbler of water will
IN short time, move from one place
to another and turn upon itself.
These movements are due according
to some authorities, to the recoll pro-
duced by the escape of vapors, by 9th
ers to a mysterious force called super
tlclal tension, existing on the surface
of liquids.
The Swiss Watch Trade.
The Economists Francois publishes
an interesting article upon the progress,
of the Swiss watch trade, which is des-
crlbed as having undergone complete.
years, this transformation being due
to the substitution of manufactures
for work in the homes of the watch
makers themselves. The opening Of
these manufactures has led to de-
crease in the cost price of the watch
and to a great increase in the sale, so
much so that at the recent Paris Ex-
hibition the official report of the inter
national jury was to the effect that,
"Switzerland occupied the first rank
as regards thermometers, watches Of.
precision, and complicated works.,
and has made great progress,
in the domain Of watches for.
common use, this progress being
due to the improvement in the equip
ment of the manufactures. The differ
ent schools for teaching the watch.
trade at Geneva, Neuchatel, la Chaux:
DIES Ponds, Loole, Bienne, St. INFER,
and Porrentruy, the various associa--
tons OF manufactures, and the Jour
nails dealing with the subject of watch
making have contributed in no small
degree to this progress, which has
been very marked in thelast six years;
the number of watches exported from
Switzerland having increased from.
1874, 234 in 1885 to 4,43l, 3O1 last;
year, these figures not Including the
works and cases exported separately
Altogether, the value of the exports
last year is calculated by the Econo-
miste Francois at "a, 100000, while
the wages are so high that many FAM
lilies earn from ELI to 916 a month";
The Production of Very Low Tenn
peratures.
An apparatus has recently been.
constructed by M. Ducretet for getting
quickly in the laboratory a. fall of
temperature 20 to so deg C. below.
zero, by means of the expansion Of
liquid carbonic acid. The inner of
two concentric vessels contains, in
alcohol, a serpentine metallic tube:
communicating through a tube with,
two stopcocks, with the carbonic acid,
reservoir outside and opening below,
into the annular space round the in
ner vessel, in which are some pieces Of:
sponge impregnated with alcohol.
This two-walled vessel with coil is en-
closed in a box. One stopcocS Icing
opened wide, the other Slightly, the,
carbonic acid passes through the coil.
as snow, and turns to gas, with strong:
cooling effect, and any OF it not va
pourized in the coil is dissolved in the.
alcohol OF the sponge. The gas es--
capes through a tube passing through,
the outer box.
An Odd Light.
To instantly obtain a light sufficient
to read the time by a watch or clock
at night without the use of Matches,
and without the danger of setting:
things on fire is an easy matter. Take
an oblong vial of the clearest of glass;,
put into it a piece OF Phosphorus
about the size of a pea, upon this
pour some pure olive oil heated to the
boiling point; the bottle to be filled
about one-third full; then cork tightly.
To use the light, remove the cork, al
low the air to enter and then recork- .
The whole empty space in the bottle
will then become luminous, and the.
light obtained will be a good one. AS.
soon as the light becomes DIM it's pow.
er can be increased by opening the
bottle and allowing a fresh supply of
air to enter. In very cold weather it,
is sometimes necessary to heat the.
vial between the hands to increase the
f1uidity OF the oil, and one bottle Will
last a winter. This ingenious contriv-
ance may be carried in the poke.
and is used by Watchmen of Paris IL.
all magazines where explosive or i'll
Hammable materials are stored.
A Table With Growing Legs
Under the heading "a Curiosity,r
the Montreal Daily Witness publishes.
the following letter from all Ontario.
correspondence had presented to
me on the 3rd of May last q small
fancy table as a birthday present.
painted black, varnished and gilded.
However, it had not been in the house.
very long before the legs were observed.
to be growing, and they are still CON
tinuing to do So. One of the legs has.
put out a shoot four inches long, upon,
which there are ten leaves. Altogeth-
er it is a very pretty table, with it's
black and gold and now the green.
think they are apple-tree leaves. T
set it out of doors occasionally, so.
that a little moisture might be given,
to it to continue the growth, as I do,
not know but it may blossom and
bring forth fruit, which would very