Improvements relating to Foot Warmers.
Year: 1892

page_text: Date of Application, 8th Nov., 1892
Complete Specification Left, 8th Sept., 1893-Accepted, 28th Oct., 1893
PROVISIONAL SPECIFICATION.
Improvements relating to Foot Warmers.
I, JUSTINE DUFOUR, Veuve ANCELIN, of 237 Faubourg St. Martin, Paris, in
the Republic of France, do hereby declare the nature of this invention to be as
follows:-
My invention relates to foot warmers, and is based upon the disengagement of
heat derived from the latent heat of fusion.
A very great number of substances have been tried for this purpose, especially
alkaline salts, and amongst the latter acetate of soda. Experience has shown that
acetate of soda produces the desired results, but renders particular precautions
necessary for preventing surfusion.
To obviate this inconvenience I employ a substance which is not
salt and
which possesses all the desired advantages; this substance is dry hydrated baryta,
also called hydrate of baryta.
This base melts at the comparatively low temperature of 75 to 80 degrees. But
for employing it in foot warmers I cause the liquefaction of the hydrate of baryta
by heating it in a water bath, with boiling water or by steam. The liquid thus
obtained is introduced into the foot warmers made of sheet iron or copper, which
have no device for obviating surfusion. It is sufficient to provide them with an
hermetic stopper or plug, or they may be soldered for the baryta serves once for
all, like acetate, as an agent for the transmission of heat.
When the foot warmers have become cool, which takes place after the solidifica-
tion of the whole mass of the baryta, they are heated again by placing them for a
certain time in boiling water or steam, when they reach a temperature above the
temperature at which the fusion of the hydrate of baryta takes place. When the
foot warmers are used they will cool, the temperature being lowered at first to from
75 to 80 degrees, whereupon the solidification commences and the temperature will
always remain between from about 75 to 80 degrees during the whole time of the
solidification.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to Foot Warmers.
I, JUSTINE DUFOUR, Veuve ANCELIN, of 237 Faubourg St. Martin, Paris,
in the Republic of France, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement:-
My invention relates to foot warmers, and is based upon the disengagement of
heat derived from the latent heat of fusion. A very great number of substances
have been tried for this purpose, especially alkaline salts, and amongst the latter
acetate of soda. Experience has shown that acetate of soda produces the desired
results, but renders particular precautions necessary for preventing surfusion.
To obviate this inconvenience I employ a substance which is not a salt and
which possesses all the desired advantages; this substance is dry hydrated baryta,
also called hydrate of baryta.
This base melts at the comparatively low temperature of 75 to 80 degrees. But
for employing it in foot warmers 1 cause the liquefaction of the hydrate of

page_text: baryta by heating it in a water bath, with boiling water or by means of steam.
The liquid thus obtained is introduced into the foot warmers made of sheet iron
or copper, which have no device for obviating surfusion. It is sufficient to
provide them with an hermetic stopper or plug, or they may be soldered, as the
baryta serves once for all, like acetate, as an agent for the transmission of heat.
When the foot warmers have become cool, which takes place after the solidi-
fication of the whole mass of the baryta, they are heated again by placing them
for a certain time in boiling water or steam, when they reach a temperature above
the temperature at which the fusion of the hydrate of baryta takes place. When
the foot warmers are used they will cool, the temperature being lowered at first to
between 75 to 80 degrees, whereupon the solidification commences and the
temperature will always remain between from about 75 to 80 degrees during the
whole time of the solidification.
.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The application of hydrated baryta as a material susceptible of receiving and
emitting heat by way of fusion, as herein set forth.
Dated this 8th dox of Santambar 1802
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.