IMPROVEMENTS IN APPARATUS FOR COOLING AIR AND FOR APPLYING THE SAME FOR COOLING AND REFRIGERATING
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Jacob Geoghegan Willans at
the Office of the Commissioners of Patents, with his Petition, on
the 24th May 1875.-A communication from abroad by Thomas
Joseph Willans, Captain in Her Majesty's Royal Engineers, residing
at Shillong, Assam, India.
I, JACOB GEOGHEGAN WILLANS, of No. 9, Saint Stephen's Crescent,
in the Parish of Paddington, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN APPARATUS FOR COOLING AIR AND FOR
APPLYING THE SAME FOR COOLING AND REFRIGERATING," to be as follows:-
This Invention relates to the compression of air by and in the presence
of water, whereby it will, while undergoing compression, be robbed of a
great part of its latent heat, and in consequence will, on its liberation, be
applicable for cooling and ventilating.
The means adopted are,―
Firstly. To compress air by water under pressure derived from a head.
or equivalent source. The water may be conducted by a pipe into a
closed vessel containing air, and discharged therein in the form of a
shower or otherwise. In this vessel the air should be retained until
compressed to a degree corresponding with the amount of head or
pressure of the water.

page_text: Secondly. The useful effect of a head of water for compressing air as
above may be increased by admitting air under pressure to the upper
level of the water in such manner that the pressure of the water at the
bottom of the pipe is increased more or less in accordance with the
amount of air pressure so applied. This may be done by having the 5
upper part of the water pipe communicating with a closed water tank
or vessel containing water, into which compressed air is admitted. Taps
and valves will be required for adjusting the passage of the water and of
the air, and these may be made self-acting by means of a float and
connecting rods or equivalent mechanism operated by the rise and fall 1
of the water supplied to either or both vessels, or to chambers in
connection therewith.
The Invention, thirdly, includes the application of the air compressed
as first described to the head of water, as secondly described previous to
its being liberated for cooling or ventilating purposes. To this end an 1
air receiver is provided, which being connected with the upper part of
the air compressing vessel and with the vessel charged with the head
water, will by suitable valves be supplied from time to time with
compressed air from the air vessel, and discharge it on to the head water,
thereby adding to the effective weight of the head of water, and con- 2
sequently increasing the pressure in the air compressing vessel.
When the required degree of compression is attained the compressed
air is allowed to discharge into the receiver and a fresh supply of air is
admitted to the compressing vessel; the water simultaneously finding an
outlet at the bottom of the vessel, and thus the process may be repeated. 2
The air that has undergone compression will conveniently be drawn off
for use from the vessel containing the head water after it has acted
as an auxiliary to the water in compressing air in the air compressing
chamber.

page_text: apparatus. This will allow of highly compressed air accumulating iņ
the air receiver, being taken out directly from that vessel, and used for.
cooling water to and below the freezing point. As this method will
require more compressing power it is preferred for ordinary cooling and
ventilating purposes to allow the compressed air from the air receiver to
act on the head of water before it is discharged for uso. The air so
compressed may be made to issue from jets into air passages, and thus
carry atmospheric air along with it for intermixture therewith into
chambers, wherein it may be utilized for cooling or ventilating.
Before the air that has undergone compression is used for cooling or
ventilating it may be passed over or in contact with substancos that
have an affinity for moisture, such as chloride of calcium or sulphuric
acid, in order to render its cooling propertics the greater.
For the purpose of refrigerating and freezing I employ an apparatus
which consists of a box or casing lined with some slow conductor of
heat, and containing a number of shallow trays made of good conducting
metal, preferably copper or galvanized iron, supported one above the
other with spaces between them for the passage of air. The trays rost
at their sides upon projections or ledges on endless chains or bands,
which are placed one at either side of the interior of the casing, and aro
supported on rollers at its top and bottom. The rollers at the top of the
casing are geared, together so that the bands may be moved simul-
taneously, and the trays kept perfectly level. The trays are somewhat
shorter than the length of the inside of the casing or box, and aro
placed alternately against each of its ends so as to admit of an air
passage at the opposite end. Cold air is caused to enter at the bottom
of the casing below the bottom tray, and passes under and over every
tray in succession, and finally escapes at the top.
For producing ice the trays are filled with water to a depth of about
1 inches or more, and are put in at the top and taken out at the
bottom. As a tray is taken out the whole of the others are lowered by
turning the gearing above mentioned to admit of another tray being
placed at the top. By this arrangement the water in the trays becomes
gradually cooled, the bottom tray which has next to be withdrawn being
acted upon by the coldest air, and the tray last introduced being acted
upon by the air which has already passed in succession under and over
all of the other trays. In the same way other substances to be con-

page_text: gealed or refrigerated may be placed upon the trays, and similarly passed
through the apparatus.
Doors are provided for introducing and withdrawing the trays. The
temperature of the air employed for refrigerating may be lowered by
liberating it from under compression or by other means.