Improvements in Barometers.
Year: 1898

page_text: PROVIDIUNAL DE MULTICATION.
Improvements in Barometers.
THOMAS HORTON, Rednal, near Barnt Green, Worcestershire. I do hereby
declare the nature of this invention to be as follows:-
I construct a tube (to contain the mercury of a barometer) having one or more
bends in the lower portion of it, so that when the atmospheric pressure rises or
falls, the lower surface of the mercury may rise or fall, and move obliquely,
according to the obliqueness given to that part of the tube in which the lower
surface of the mercury moves. The open end of the said oblique portion of the tube
I cover with material that will let air into, and out of the tube, but prevent the
mercury escaping when the barometer is being carried.
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The reading of the barometer is taken at the lower surface of the mercury
in the said oblique portion of the tube, near to which I fix the scale.
At the top
of the vertical part of the tube I have a bulb or short enlargement, large enough
to contain a quantity of mercury, equal to (or more than) that which may rise
or fall in the oblique part of the tube in accordance with the pressure of the
atmosphere upon the lower surface of the mercury.
Dated this Nineteenth day of April 1898
THOMAS HORTON, Rednal, near Barnt Green, Worcestershire. I do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
I will describe my "improvements in barometers" as applied to a barometer
having the tube bent as shewn on the accompanying drawing, but tubes bent
to various other shapes may be used for my said improvements, or some of them,
A is a tube (preferably made of glass) having that part C of it (of any suitable
length) bent to an oblique position in which the lower surface B of the mercury
moves, so that when the atmospheric pressure rises or falls, the lower surface B of
the mercury may rise or fall, and move obliquely, according to the obliqueness
given to that part C of the tube, in which the lower surface B of the mercury
rises and falls.
At the top of the tube I have a bulb, or short enlargement F (hereinafter called a
cylindrical bulb) in which the upper surface H of the mercury rises and falls, the

page_text: said cylindrical bulb being of larger diameter and capacity than the diameter and
capacity of that part of the tube in which the lower surface B of the mercury rises
and falls, so that the upper surface H of the mercury may rise and fall but slightly,
compared with the rise and fall of the lower surface B of the mercury: The
open end D of the part C of the tube, I cover with material that will admit air into,
and out of the tube, but prevent the mercury escaping when the barometer is
being carried.
"
Direct readings" of the barometer are taken at the lower surface B of the
mercury, near to which I fix the scale E. The said scale is fixed to the frame of
the barometer, but as the frame is not shewn on the drawing I have (to illustrate
how "readings" of the barometer are taken) shewn the scale in about the position
it would be as regards that part of the tube in which the lower surface B of the
mercury rises and falls, and readings of the barometer are taken.
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According to the barometer shewn on the drawing, a rise or fall in the
atmospheric pressure, equal to one inch in height of mercury shews 13 ins. on the.
scale: It is obvious that when the atmospheric pressure upon the lower surface B
of the mercury increases, the said lower surface of the mercury falls, and rises
when the atmospheric pressure diminishes, as shown by the scale E. It will be
seen that 29.50 ins. is the " reading" of the barometer shewn on the drawing,
G is an ordinary barometer air-trap.
It will be understood that there is the usual vacuum above the upper surface
of the mercury.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is: —
.1. In a barometer, the lower part of the tube bent to an oblique position in
which the lower surface of the mercury rises and falls.
2. In a barometer, the upper surface of the mercury rising and falling in a
cylindrical bulb of larger diameter and capacity than the diameter and capacity of
that part of the tube in which the lower surface of the mercury rises and falls
near to which the scale is fixed and direct "readings" of the barometer taken at
the lower surface of the mercury.
Dated this 18th day of Tannam 1900.