IMPROVEMENTS IN THE PRODUCTION OF ICE, AND IN APPARATUS FOR THE SAME
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at
the Office of the Commissioners of Patents, with his Petition, on
the 1st July 1870.-A communication from abroad by Mr. Koehler,
of 13, Boulevart St. Martin, Paris..
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE PRODUCTION OF ICE, AND IN
APPARATUS FOR THE SAME," to be as follows:
This Invention relates to improvements in the production of ice and
also in apparatus for the same, based on the same principle as those now
in use, viz., on the absorption of heat by the evaporation of volatile
liquids in vacuo.
The liquid I use by preference in the apparatus consists of hydrochloric
ether (chloride of ethyle), which boils at a temperature of 54 degrees
Fahrenheit, the vapor having at the low temperature of 4 degrees below
zero, Fahrenheit, a tension of eight inches of mercury. The latent heat
of its vapor is represented by 586 Fahrenheit units of heat and much
above that of ordinary sulphuric ether.

page_text: The Invention further consists in the application for refrigerating
purposes of vinous and methylic ethers, whose equivalents are repre-
sented by four volumes of vapor and boiling at low temperatures; also
of chloride of ethyl, bromide of ethyl, formiate of ethyl, acetate of
methyl, formiate of methyl, chloride of methyl, iodide of methyl,
bromide of methyl, and monochloruretted chloride of methyl. I may also
use for refrigerating purposes other substances boiling at low tempe-
ratures, and having a gaseous equivalent of four volumes, such as
amylene, ethylamin, and methylamin, bicarbonated, monochloruretted,
and bichloruretted hydrogen.
I have found that the above liquids generally possess a much greater
latent heat on evaporation with an equal weight compared with ether or
other vaporizable fluids, whose equivalent is represented by two volumes
of vapor only, viz., ether, methylic ether, sulphuret of carbon, and
liquefied sulphurous and carbonic acids. If their volumes be compared
it will be found that the amount of heat absorbed in the production of
about 62 cubic inches of vapor at 32 degrees Fahrenheit and at the
atmospheric pressure (30 inches) is equal to 1.700 units in the case of
liquids having a gaseous equivalent of four volumes, while 62 cubic
inches of vapor of liquids having an equivalent of two volumes will only
absorb 1.198 units of heat. Thus the liquids first mentioned, boiling at
the same or nearly the same temperatures, may be much more advan-
tageously used for refrigerating purposes in apparatus where a vacuum
is formed and in which the effect is determined by the volume of vapor
displaced by the air pump in a given time.
The following is a description of the improved apparatus of this
Invention for producing ice :-
Figure 1 shows a front view of the apparatus; Figure 2, a plan;
Figure 3, a section on line 1, 2, Figure 2; Figure 4, a section on line
3, 4, Figure 2; Figure 5, a section on line 5, 6, Figure 2; Figure 6
shows a part detached on an enlarged scale. The reference letters apply
to all the Figures.
A, A, freezing chamber of wood lined with copper; B, B, series of
worm tubes; D, D, air pump; d, d, hollow chamber for heating the
lower part; E, E, pipes connecting the pump with the worms B; F, F,
condensing bath; G, G, refrigerating worm tube; H, H, pipe connecting
the pump and worm G; J, reservoir or regulator; K, K, pipe connecting
pipe G with reservoir J; L, return pipe connecting the reservoir with.

page_text: worm tubes B, B; M, M, inlet orifices; N, N, stop cock; O, air discharge
cock; P, P, vacuum guage; Q, pressure guage; R, pipe connecting
pump with worm tubes B; S, discharge pipe of reservoir; T, inlet
orifice of water to the condensing bath; U, outlet for same; V, V,
freezing vessels; X, Figure 6 shows a full-sized view of one of the
injection orifices M.

page_text: hot water is introduced for licating the pump in order to prevent a too
rapid condensation of the ether at starting. The reservoir J contains a
reserve of ether, and is provided with an air discharge cock o, safety
valve and pressure guage Q, as also a float for regulating the flow of the
liquid at pipe L, L.
The chief feature of the apparatus consists of the worm tubes by the
aid of which a very large surface is brought in contact with the freezing
liquid. The surface of ether contained in the worm tubes is also very
considerable, the evaporating surface being also greatly augmented by
the form of the injecting orifices. The whole is thus arranged to ensure
a rapid volatilization. The hydrochloric ether which boils at 54 degrees
Fahrenheit possesses at a temperature of 4 degrees below zero, Fahren-
heit, a tension of vapor of 8 inches of mercury. In comparing the results
of the use of equal weights of hydrochloric ether and ordinary ether for
the production of ice it will be found that the former will produce an
amount represented by 148, while ordinary ether is represented by
91 only.
Conceding that the pump produces theoretically a vacuum or a
displacement of 16.500 cubic inches of vapor per minute the heat
absorbed would be × 1.700 = 1.273 units, and an absorption of
76.500 units per hour
46.500
62
==
To congeal 62 cubic inches of water at an average temperature of 62
degrees Fahrenheit it is necessary to abstract from it 312 + 68 = 380
units. This improved apparatus will thus theoretically congcal
× 62
76.500
380
= 12.500 cubic inches (abot) of water per hour, and supposing
that in practice the product be 50 per cent. only of the amount above
stated, this would give 6250 cubic inches per hour.