Improvements in Apparatus for Testing Milk and other Substances.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Testing Milk and other Substances.
We, THE DAIRY OUTFIT Co., LTD, of 251, 253, and 255, Pentonville Road,
London, N., and WILLIAM THOMAS WEBSTER, of 252, Caledonian Road, London,
N., Analytical Chemist and Bacteriologist, do hereby declare the nature of this
invention to be as follows;
-
This invention relates to apparatus for testing the amount of fat in milk by
mixing chemicals in a test tube with the sample of milk to be tested and after-
wards separating the parts of which the mixture is composed by centrifugal
action.
These improvements can also be used for investigating other substances.
We take a narrow test tube of glass on which we mark a graduated scale.
We make a small chamber at the top and we widen it out below into a reservoir.
The said reservoir is constricted in one or more parts. These constrictions cause
friction which increases the heat and a more thorough mixing of the milk and
chemicals while being shaken. At the bottom of the said reservoir we provide
a neck for a rubber stopper in the usual way.
The said test tube when complete with chamber reservoir and neck is of such
a size that when the proper quantity of milk and chemicals are placed therein
there is considerable space for them to move up and down while being shaken.
We also arrange the whirling machine so that the test tubes while therein
do not come in contact with metal. We place them in tubes made of non-
conducting material which we can also if necessary surround with non-conducting
material to prevent the heat generated in the tubes from being dispersed.
Dated this 1st day of August 1899.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Testing Milk and other Substances.
We, THE DAIRY OUTFIT, COMPANY, LTD., of 251, 253, and 255, Pentonville
Road, in the County of London, and WILLIAM THOMAS WEBSTER, of 252, Cale-
donian Road, London, aforesaid, Analytical Chemist and Bacteriologist. do
LP 81

page_text: 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 follow-
ing statement: —
This invention relates to apparatus for testing milk and other substances
wherein the substance to be tested is mixed with chemicals which combine with
some of the constituents and not the others, the parts of the mixture being
subsequently separated by centrifugal action.
In such apparatus as heretofore made and used for testing the amount of fat
in milk it has been found necessary, in order to effectively carry on the opera-
tion, to immerse the tube, containing the mixture of milk and chemicals, in a
hot water bath so as to raise the temperature of the mixture to that required to
liquify the fatty constituents. This is a somewhat tedious process and one of
the objects of our invention is to overcome this disadvantage.
Another object of our invention is to prevent the heat generated in the tubes
from being lost by conduction when in the whirling apparatus.
In the accompanying drawings Fig. 1 is a partly sectional elevation of the
whirling apparatus, and Fig. 2 shows to an enlarged scale a tube constructed
according to our invention and so made as to provide for the conservation and
reinforcement of the heat developed by the reaction of the chemicals with the
milk or other substance, thus keeping the fatty constituents in the liquid state.
In making our testing tube as shown in Fig. 2 we take an ordinary narrow
glass test tube on which we mark a graduated scale A, and at its closed end we
blow or otherwise form a small chamber B. Near to the mouth C of the tube
we widen it out into a reservoir D in which we form one or more constrictions d,
or in place of constrictions, such as d, we may form obstructions or ridges or
the like on the inside of the said reservoir. The completed testing tube is of
such capacity as to provide ample space for the contents to move up and down
when shaken.
The constrictions or ridges d offer obstruction surfaces to the passage there-
over of the contents of the tube and when the latter is shaken in the ordinary
way to effect an intimate mixture of the contents the obstruction offered by these
constrictions or ridges effects a thorough mixing of the chemicals with the milk
or other substance under treatment, and the heat developed by the reaction is
reinforced by the heat produced by the friction of the moving liquid over the
obstruction surfaces.
A rubber stopper is fitted in the mouth C of the tube in the ordinary way and
the stoppered tubes are fitted into heat non-conducting containing tubes É (see
Fig. 1) which latter we preferably make of mill-board, but any suitable non-
conducting material may be used to contain the testing tubes and prevent the
conduction of heat therefrom.
The whirling apparatus, as shown in Fig. 1, is made in the form of a conical
receptacle F having a central dished well f, the walls of said well being pierced
with holes f to receive the containing tubes E. The well is closed by a disc
cover G and the apparatus is mounted on a spindle in the ordinary way.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is:-
(1) In apparatus for testing milk and other substances, a testing tube having
a small chamber at its upper end and an enlarged reservoir near its mouth, said
reservoir having constrictions or obstruction surfaces on its inner side, substan-
tially as described and for the purpose stated.
(2) In apparatus for testing milk and other substances, mounting the testing
tubes in non-conducting containers fitted into the whirling apparatus, sub-
stantially as and for the purpose herein before described with reference to Fig. 1
of the accompanying drawings.

page_text: (3) Apparatus for testing milk and other substances constructed and arranged
substantially as and for the purpose hereinbefore described with reference to
the accompanying drawings.
F. W. GOLBY,
Patent Agent, 36, Chancery Lane, London, W.C.,
Agents for the Applicants.