New-York tribune., 1880-10-03
HINTS FOR BATHERS.

HIN 10 FUN DA uEhc.
According 10 The London Lancet it is i'm
portant to recognize that the only virtues OF
water as used by the bather are two-namey
its value as a cleansing agent, and as sur
face stimulant. In this last capacity 1t simply
acts as a medium affecting the temperature or
the part to which it IL applied, or which Is
immersed in il. Right views of fact In refer
epce to this matter are important, because
there can be no question that some persons
Overrate the uses OF cold water, and run con-
siderable risks in their pursuit or them. Every
beneficial action that can be exerted by bath
is secured by simply dipping in the sea, or
very moderate atfusl0n OF cold water Except
in cases of high fever, when it Is desired to
reduce the heat of the body by prolonged con-
tact with cold bath of any considerable du-
ration is likely to be injurious.
Then, again, 1t is necessary 10 recognize the
risk of suddenly driving the blood from the
surface in upon the organs. The plunge. or
dip or Shower" or douche," Is intended
TO produce mOmentary depression OF the
temperattlre of the surface In the hope OF Oc-
casioning a reaction which shall bring the blood
back to the surface with increased vigor, and
almost instantly. IL this return does not take
place if, in "a word, redness OF the skin Is
not a very rapid consequence OF the INNER
sion, il is impossible that the bath can have
been useful, and in nine cases out OF ten when
the surface is left white or cold 1t does harm.
The measure of value Is the redness which
ensues promptly after the bath, and this reac.
ton should be produced without the need OF
much friction, or the bath Is not worth TAX
ing The rubbing employed TO recover the
circulation lost by the bath would probably
have done more good without lt
Another effect of the bath when it acts prop
erly Is TO stimulate the nervous system, through
the vast series of its terminal fbres which are
distributed in the skim In this way also the
action must be very rapid, or 1t Is not et1ca-
cious. Unless the vigor of energy Is quickly
called out, the agent is useless and II 1t pro-
dam ion n nRfz
mischievously, and lowers the power 1t is in
tended to stimulate and augment.
RUBBER MOULDS AND STAMPS.
In an admirable lecture by Mr.. Thomas
Bolas, Fellow of the Chemical Society before
the London Society of Arts the following plan
of making casts or mOuldlngs or ph0totyplc
reliefs in vulcanized rubber Is given. Take
an ordinary type-metal cast or mould pro-
duced by Photographic agencies from the
original negative. Tie first step Is very
slightly to oil the mould. after which black
lead is applied to the surface, and the excess
is polished off by means or a soft brush. A
sheet of mixed rubber, previously sottened by
heat, is next applied 90 the prepared surface
of the mould and curing is effected by means
Of a small hOt-press, INTO which the mould
and rubber are placed. This press consists OF
a cast-irOn fsh-kettle, upon the bottom or
which rests slab of type-metal an inch
thick. Inside the kettle Is placed small
press, like copying press In miniature. by
the side of the press stands a small iron cup,
containing glycerine, and in this fluid is i'm
mersed the bulb of a thermometer, the stem
of which projects through a hole III the cover
of the kettle. BY means OF small gas stove
heat can be applied TO the apparatus, and it
is easy so to adjust the gas supply that the
thermometer shall indicate a tolerably con-
slant temperature of, say, 140' or 1902 CEN
tigrade. Most qualities of mixed rubber Will Will
become fairly well cured by being heated
and any tendency toward adhesion to the mould
is obviated by the preparation with oil and
black lead.
This apparatus is also extremely well adapted
for curing the india-rubber stereotypes
stamps, now so extensively used for lndorse-
ment and other purposes. To make these
stereotypes, a reverse or mould Is made from
the types this being taken IN plaster OF Paris,
or better still, in metal. When plaster is en-
poyed it is well to harden 1t, by saturating
il with an alcoholic solution of shellac, and
again driving. The soft mixed rubber is then
forced into the mould, after which the curing
may be effected III the hot press.