Improvements in Olinical Thermometers.
Year: 1897

page_text: Date of Application, 25th Feb., 1897
Complete Specification Left, 26th. Mar., 1897-Accepted, 1st May, 1897
Improvements in Olinical Thermometers.
I, JAMES JOSEPH HICKS, of 8 Hatton Garden, in the County of London,
Meteorological Instrument Manufacturer, do hereby declare the nature of this
invention to be as follows:-
The invention has for its object an improved construction of clinical thermometer
with a view to render the re-setting of the same more easy than is the case with
clinical thermometers as heretofore constructed.
Heretofore clinical thermometers have been made with what is known as an
"indestructible index," which is obtained by making a single knife-edge contraction
in a chamber in the bore at a position more or less near the bulb, such contraction
acting, on the cooling of the mercury in the bulb, to separate the portion of mercury
above the contraction from that below the same.
With this construction of clinical thermometer it was necessary to make the said
knife-edge contraction so acute as almost to close the bore at that part, as otherwise
the separation of the mercury above the contraction from that below would not take
place on the cooling of the same but the entire column of mercury would pass below
the said contraction.
The above-named construction of clinical thermometer renders it very difficult to
re-set the same on account of the violent shaking or swinging necessary to cause the
mercury in the tube to pass below the said contraction.
According to my present invention I obviate this difficulty by making two such
contractions in the tube in chambers at a short distance from each other instead of
only one, by which means it is unnecessary to make such contractions so acute as
is necessary with the single knife-edge contraction heretofore used. With this
construction the two chambers containing the said contractions and the bore between
them always remain filled or nearly so with mercury.
It will be evident that more than two chambers with such contractions may be
provided, but it is unnecessary to employ more than two.
Dated thin 05th dan of Tahu1007
COMPLETE SPECIFICATION.
Improvements in Clinical Thermometers.
I, JAMES JOSEPH HICKS, of 8 Hatton Garden, in the County of London,
Meteorological Instrument Manufacturer, do hereby declare the nature of this
invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
The invention has for its object an improved construction of clinical thermometer
with a view to render the re-setting of the same more easy than is the case with
clinical thermometers as heretofore constructed.
Improvements in Clinical Thermometers.
I, JAMES JOSEPH HICKS, of 8 Hatton Garden, in the County of London,
Meteorological Instrument Manufacturer, do hereby declare the nature of this
invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
The invention has for its object an improved construction of clinical thermometer
with a view to render the re-setting of the same more easy than is the case with
clinical thermometers as heretofore constructed.

page_text: Heretofore clinical thermometers have been made with what is known as an
"indestructible index," which is obtained by making a single knife-edge contraction
in a chamber in the bore at a position more or less near the bulb, such contraction
acting, on the cooling of the mercury in the bulb, to separate the portion of mercury
above the contraction from that below the same.
With this construction of clinical thermometer it was necessary to make the said
knife-edge contraction so acute as almost to close the bore at that part, as otherwise
the separation of the mercury above the contraction from that below would not take
place on the cooling of the same but the entire column of mercury would pass below
the said contraction.
The above-named, construction of clinical thermometer renders it very difficult to
re-set the same on account of the violent shaking or swinging necessary to cause the
mercury in the tube to pass below the said contraction.
--
My present invention is illustrated in the accompanying drawings, in which
Fig. 1 is a longitudinal sectional diagram of a clinical thermometer showing my
invention applied to that class of clinical thermometer known as the "Non plus ultra,"
in which the contraction for producing the "indestructible index" is very near the
bulb.
Fig. 2 is a longitudinal sectional diagram showing my invention applied to an.
ordinary clinical thermometer in which the contraction for producing the
"indestructible index" is at a greater distance from the bulb, and
Fig. 3 is a similar section showing a modification.
According to my present invention I obviate the difficulty hitherto experienced in
re-setting clinical thermometers provided with an "indestructible index"
following improved construction.
by the
I make two chambers bb within the bore of the tube a at a short distance from each
other, and within each of such chambers bb I make a contraction 6'. By making two
chambers within the bore of the tube, each provided with a contraction, instead of
only one chamber and one contraction, I am enabled to make the two contractions
employed by me less acute than is necessary with the single knife-edge contraction
heretofore used.
With my improved construction of clinical thermometer, by reason of the contractions
employed to produce the "indestructible index" being less acute than the single
contraction heretofore used for such purpose, the mercury is enabled, when the
thermometer is swung or shaken, to pass such contractions much more readily than
heretofore, thereby greatly facilitating the re-setting of the thermometer.
It may be remarked that with the present improved construction of thermometer,
the chambers b b containing the contractions 6' 6' and the portion of the bore of the
tube a between them, will always remain filled or nearly so with mercury, and
although the contractions 6' 6' will allow the mercury to pass more freely than the
single contraction heretofore used, they do not in any way interfere with the
separation of the "indestructible index " from the column of mercury on the cooling
of the latter in the bulb c.
These chambers 6 with contractions 6' may be made more or less near to the bulb c,
as shown in the drawings.
In the modification represented at Fig. 3, in lieu of making two contractions in a
single bore, I insert between the bulb c and the tube a, a short length of double-bore
tube a', the two bores of which communicate with the bulb c and also with the bore of
the tube a, and I make a chamber b and a contraction 6 within each of such bores
of a similar character to those shown at Figs. 1 and 2.
It will be evident that more than two chambers with such contractions may be
provided, but it is unnecessary to employ more than two.
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 :-
1. A clinical thermometer having two or more chambers formed within the bore of

page_text: the tube and a comparatively open contraction within each chamber, substantially as
herein shown and described and for the purpose stated.
2. In clinical thermometers, the combination with a thermometric bulb and a tube
having a bore communicating with said bulb, of two or more chambers interposed
between the indicating part of the tube and the bulb, and a comparatively open
contraction within each of such chambers, substantially as herein set forth and for the
purpose stated.
3. The improvements in clinical thermometers substantially as herein shown and
described and for the purpose stated.
HARRIS & MILLS,
23 Southampton Buildings, London, W.C., Agents.