IMPROVEMENTS IN STEAM GENERATORS, AND IN APPARATUS IN CONNECTION THEREWITH
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by Thomas Mills and William
Bryce at the Office of the Commissioners of Patents, with their
Petition, on the 18th November 1870.
We, THOMAS MILLS, of 20, Ashmead Road, Deptford, in the County
of Kent, and WILLIAM BRYCE, of London and Manchester, Gentleman,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
STEAM GENERATORS, AND IN APPARATUS IN CONNECTION THEREWITH," to be as
follows:-
Our Invention relates, firstly, to fitting a self-acting clack or valve to
a coil or coils of tubing (said coil to form the whole or part of generator)
for the purpose of promoting the circulation of water through the coils
and to prevent superheating of the steam when the pump is not acting.
We make the generator of a coil of tubing preferably of the spiral form
and enclose it in a jacket forming the box. Over the jacket we place
a water and a steam chamber, the water being brought down by a tube
outside the generator to the bottom thereof where it passes through the
clack or valve by its own pressure, the clack being instantly closed on
the water being expanded by coming in contact with the heated tubing,
the water being forced on through the coil by the steam generated until
it is all converted into steam when it passes out of the coil into the
steam and water chamber above, thus a perfect circulation of water is

page_text: obtained through the coil when the engines are stopped and con-
sequently the pump not in action. In some cases the water chamber is
in direct communication with the coil so that the fire will play all
round it between the inner surface of the coil and the outer surface of
the chamber. This generator can be constructed either with or without
the water chamber, but with a small chamber for holding a reserve of
steam, which chamber can be placed inside or outside the generator so
that the action of the clack could be kept up by a pressure of water
raised above the level of itself and allowing the pressure of steam to go
down in the steam chamber when the engine is not working, and
thereby prevent the tubing being heated to too great an extent as it
would otherwise do. This form of generator is very suitable to steam
launches, fire engines, and locomotives on account of its lightness and
economy. For steam boats this generator can be worked without any
water chamber by feeding the coil with water from the feed pump
through the clack which would be fixed in the bottom of the boat
and acted upon by the external pressure of water, at the same time
blowing off the steam in the chamber to reduce the pressure.
The second part of our Invention relates to an apparatus for showing
the height of the water in the generator at all times by means of one
cock. The cock has a long stem which passes through a stuffing box
attached to the boiler's skin so that it can be turned in any direction.
The inner end of the stem is bent or curved, and by merely turning the
cock and stem round for its bent end to dip into the water the height of
the same will be indicated, which height can be read from a scale by
means of a finger or index hand. This construction and arrangement
of indicator cock is applicable to all descriptions of boilers; it can be
worked from the outside by the index above described or by a separate
handle. This cock can also be arranged with a float or ball on the
surface of the water within the boiler which will act upon the finger or
index outside the boiler, showing at a glance the position of the water
in the boiler, thus dispensing with all taps and water guages which are
expensive and liable to get out of order; it also has the advantage of
permitting an inexperienced person to attend to a boiler with perfect
safety, he having merely to attend to one indicator.