IMPROVEMENTS IN THE MEANS AND APPARATUS FOR SUPPLYING BOILERS WITH WATER
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by William Alexander Lyttle at
the Office of the Commissioners of Patents, with his Petition, on
the 12th March 1868.
I,. WILLIAM ALEXANDER LYTTLE, of the General Post Office, London,
in the County of Middlesex, Member of Society of Engineers, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE MEANS AND APPARATUS FOR SUPPLYING BOILERS WITH WATER," to be as
follows:-
A steam-tight cistern is provided above the level of the water in the
boiler and is fitted with two pipes, one of which leads from its bottom
to the water in any part of the boiler below the water level (to be called
the "water pipe "), whilst the other (to be designated the "steam pipe ")"
communicates between the top of the cistern inside and the interior
of the boiler, its lower end terminating in the plane in which the surface
of the water is intended constantly to stand. Supposing the cistern
is full of water and the lower ends of the two aforesaid pipes are closed
by the water in the boiler, no water can then escape from the cistern
into the boiler. When however the water in the boiler falls below its
proper level the steam pipe is thus opened to the steam, which

page_text: passes through it to the top of the cistern, and the water in the cistern
is thus allowed to gravitate into the boiler. The continuity of these
pipes is made and broken alternately by the working of a three or
four way cock, sluice, or other valve. When such valve has shut the
passages below it leading into the boiler, it has at the same time
opened a communication between one or both of the cistern pipes above
the valve and the reservoir of water from which the supply of water
is to be obtained. If this water is cold it will, when the valve opens
the way, rush into the cistern by suction, owing to the condensation of
steam in the latter; in this case a three-way cock or valve will suffice,
viz., a valve which will in one position open both the cistern pipes to
the boiler, and in the next position will open only the communication
between the water pipe of the cistern and the pipe leading to the
water in the reservoir.
.
It may be found however a still more efficient arrangement to fit
the cistern with two water pipes, viz., one as already described for
running the contents of the cistern into the boiler, and the other for
sucking in a fresh supply of cold water; the latter should rise to near
the top of the cistern inside, and be fitted with a rose or any other
means of breaking up or spreading out the incoming supply of cold
water, so as to cause an instantaneous condensation and vacuum. If
the feed water is hot it may be necessary either to subject it to such
pressure as will cause it to rise into the cistern each time the valve is
opened, or else to place a reservoir above the level of the cistern and
to employ a four instead of a three way valve, in order that when the
valve opens a communication between the water pipe of the cistern and
the bottom of the reservoir it may at the same time open the steam
pipe of the cistern to the atmosphere. By this means boiling water
will be permitted to gravitate from the reservoir into the cistern. The
herein-before mentioned valve may be actuated either by hand only,
by the engine worked by the boiler, or by a separate donkey engine.
When it is worked by the principal engine it may be desirable to
arrange the connexion between it and the engine in such a way that
when the engine is at rest the connexion can be broken and the valvo
separately worked by the hand so as to keep the boiler full.
In the case of marine or other boilers placed close together one
donkey engine will suffice to work a large number of valves; for
instance, all the valves of the cisterns attached to a row of boilers may

page_text: be worked by a rod running the whole length of the series, and propelled
either by the principal engine or by a separate donkey engine.
Instead of the water pipe of the cistern passing direct from the valve
down into the water of the boiler it can either be jacketed with an
arrangement for taking up the heat of waste steam, or it may be
passed through or round the base of the flue on its way to the boiler,
so as to become heated with the waste gases passing away from the
boiler tubes.