Apparatus for Measuring the Depth of Water at Sea.
Year: 1899

page_text: Date of Application, 2nd Nov., 1899-Accepted, 30th Dec., 1899
COMPLETE SPECIFICATION.
Apparatus for Measuring the Depth of Water at Sea.
I, HANS HENRY LIPPMANN, of 33, Randolph Gardens, Salisbury Road, Dover,
in the County of Kent, Engineer, 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:-
By means of the following arrangement of apparatus, the depth of the sea may
be measured electrically, without stopping or delaying the progress of the vessel
in any degree. The principle of the apparatus is based upon the measurement,
in a special manner, of the electrical resistances which occur with different
pressures of water, and the calculation therefrom of the depth of the sea, or in
other words, the height of the column of water present.
There are already mechanical arrangements for ascertaining the depth, from the
pressure, of the water. These apparatus, however, have not proved trustworthy,
because the mechanical arrangements were defective, and therefore no absolutely
reliable figures were obtained in practice. One such arrangement of measuring
apparatus, which measures a quantity of air compressed by means of an increased
pressure of water, and fixes the depth of water from the amount of compression
of the air, is very complicated, and does not possess the qualities which are
requisite for a truly reliable and evenly working depth-measurer for water.
The present invention is based on a different principle therefore, to those of
the ordinary methods of measuring depths, and makes use of electricity, and
measures, by means of the electrical resistance of a wire, the height of a column
of air varying with the depth, or pressure of the water.
The construction of the apparatus will be readily understood on reference
to the accompanying drawing:-
Enclosed in a metal tube e is a glass tube f. This glass tube is closed air-
tight, at its upper end, by a plug of hard rubber d. Between the hard-rubber
plug, and the plug g at the lower end of the glass tube, a very thin wire of
German silver is stretched. The water is allowed to enter the glass tube by
the holes or perforations 11 12 &c. in the casing and m² m² m³ in the tube f
The metal tube is closed at its lower end by the inverted metal cap to which
is suspended the cylinder b. In this cylinder there is a piston a, to the lower
end of which is attached a heavy weight of from 30 to 50 pounds. In the upper
end of the said cylinder is fitted a hard rubber piece or block, to the lower side
of which is fastened the platinum peg h. This platinum peg is connected to an
electric battery and bell by means of the conducting wire k. So soon as the
weight touches the bottom of the sea, the upper end of the piston a comes into
contact with the platinum peg h, and forms an electric circuit, which sets the bell
in action.
This signal arrangement for indicating the reaching of the bed of the sea,
does not fall within the scope of the present invention, and has nothing to do
with the actual measurement. It is, however, necessary to make mention of it,
in order that the entire apparatus may be thoroughly understood in all its bearings.
CD
077

page_text: The upper end of the German silver wire of the glass tube is in connection,
by means of the conducting wire o, which passes through the hard rubber plug or
stopper d, with an electric battery, a measuring bridge, and a galvanometer. The
deeper, now, that the apparatus sinks in the water, so much the shorter will be
that portion of the German silver wire, which the electric current has to traverse,
that is to say, the resistance of the electric circuit will be the smaller, the deeper
the apparatus is in the water.
In order, therefore, to measure the depth of the sea, the apparatus is sunk to
such a depth that the lower end of the glass tube f is under water, the electric
circuit is closed, and the electric resistance is measured; the apparatus is then
allowed to sink until the bell is caused to sound, and the resistance is then again
measured. The result of the first resistance measurement will then be deducted
from the second, and, from the difference, the depth of the sea will be easily
ascertained by means of a reference table.
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:-
An apparatus for measuring the depth of water at sea, characterized by the fact
that the length of a column of air variable with the depth or pressure of the
water, is measured by means of the electric resistance of a wire a passing
through this column of air, and from which wire the electric current from an
insulated conducting wire passes into the water, which cuts off the said column
of air.
Dated thin and N
1900