IMPROVEMENTS IN APPARATUS FOR OBTAINING FRESH WATER FROM SEA WATER
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by John Matthias Ollis at the Office of
the Commissioners of Patents, with his Petition, on the 30th November
1863.
I, JOHN MATTHIAS OLLIS, of Plymouth, in the County of Devon, Chief
Engineer in the Royal Navy, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN APPARATUS FOR OBTAINING FRESH WATER FROM SEA
WATER," to be as follows:-
The first part of my Invention consists in the construction and employment,
as hereafter described, of a self-acting valve in surface condensers for distilling
sea water. This valve regulates the supply of steam, and retains within the
condenser the distilled water until it becomes cold. To effect this I fit a.
condenser with upright tubes within a cistern containing the sea water. I
feed the cistern by an inlet and outlet from the sea, as in those condensers
known as Grant's condensers, and to prevent the radiation of heat into the ship,
cause the sea water to flow freely round the condenser and through the tubes.
The steam is on the outside of the tubes. The valve is loosely fitted, and is
opened freely by the pressure of the steam acting upon it in its passage to the
condenser; a float is connected to the valve by a rod and lever, and its weight
acts against the steam and closes the valve. Its action is to throttle the
steam, but not to shut it entirely off. When the condenser is about half full.
of distilled water, the steam valve is wide open, and it is nearly closed when.
the condenser is one-third full. Two or more tubes are omitted to leave room.
for the action of the float. I do not confine myself to any particular valve,.

page_text: for instance, in some cases I employ a valve closed by the steam, and held
open by a spring and set screw.
The second part of my Invention consists in the employment of a refrigerator,
in which the distilled water is made to coudense the vapour of the water used
for condensing the steam. The refrigerator is fixed sufficiently high above the
condenser to supply the ship with water without pumping. The distilled water
is forced up into the refrigerator by the pressure of the steam within the con-
denser. That pressure will increase as the distilled water accumulates in the
condenser by the rising of the float, allowing the steam valve to open wider
until the pressure of the steam within the condenser overcomes the pressure
due to the height of the refrigerator, when a regular stream of water will be
discharged into it. A small tank placed on the top of the receiving tank will
answer the purpose. The small tank is divided by a number of perforated
shelves, and a pipe from the top of the cold water cistern, or from an air
vessel on the top, conveys the vapour of the sea water that has been used for
condensing the steam into the side of the tank or refrigerator. The distilled
water is discharged into the top of the refrigerator filters through the divisións
in its passage, condenses the vapour" of the sea water, and falls into the
receiving tank. By this arrangement water is distilled very quickly as cold
as the sea water, and free from the unpleasant flavour of ordinary distilled
water; it is fit for immediate use for drinking or otherwise, and is not liable to
imbibe the bad air of the ship. There is not any leakage of steam into the
ship from cocks, as the only steam cock required is on the boiler.