IMPROVEMENTS IN APPARATUS FOR TAKING SOUNDINGS FOR NAVIGATING AND OTHER PURPOSES
Year: 1879

page_text: LETTERS PATENT to Thomas Bassnett, of Liverpool, in the County of Lancaster,
for the Invention of "IMPROVEMENTS IN APPARATUS FOR TAKING SOUNDINGS
FOR NAVIGATING AND OTHER PURPOSES."
"
PROVISIONAL SPECIFICATION left by the said Thomas Bassnett at the
Office of the Commissioners of Patents on the 9th June 1879.
THOMAS BASSNETT, of Liverpool, in the County of Lancaster. IMPROVEMENTS
IN APPARATUS FOR TAKING SOUNDINGS FOR NAVIGATING AND OTHER PURPOSES."
The object of this Invention is to secure correct soundings without the slackening
of the speed of the ship requisite with the somewhat defective and very expensive
apparatus at present in use. The principle of my Invention consists in causing
water or any intermediate liquid to be forced into an air chamber by the pressure
of the sea water at great depths, compressing the air into a smaller volume, that
volume being exactly commensurate in inverse geometric ratio to the pressure.
The water or other liquid once forced to overflow into the air chamber remains at
the bottom of the air chamber, and can be measured at leisure after the apparatus
has been withdrawn from the sea, and in this way the exact amount of compression
and consequently the pressure at the greatest depth can be read off on a scale, or
the volume of water that has overflowed into the chamber can be measured. The
form of my experimental apparatus, which may be materially departed from, consists
in a vertical glass tube with open ends. The lower end is in communication with
the water to be sounded, the upper opens into a glass chamber surrounding the
tube and hermetically closed, except through the aforesaid glass tube, and a stop
cock at the bottom. For greater accuracy it may be desirable to contract the
orifice of the glass tube opening into the chamber, and in practice instead of making
the chamber entirely of glass I have made it in my experimental apparatus and
may continue to make it of a simple tube closed at the top end and fixed into a
metallic socket at the other end. This socket, by means of a series of small holes,
communicates with a chamber below, out of which comes the stop cock; both
socket and chamber are pierced by the glass tube, which is hermetically packed so
as to admit no water past its exterior into the outer glass tube. The whole is encased
in a metallic case or sinker with a preferably hemispherical hinged lid at bottom
CD 037

page_text: of solid metal containing a valve which freely admits water, and will also admit
any mud, sand, or gravel that the apparatus strikes against, closing automatically
the instant the apparatus begins to rise, so as to hold the said mud, sand, or gravel
for after examination.
There is also attached to the sinker a cone with two or more washers of leather
or other suitable material to pick up portions of the bottom and to bring the same
to the surface, and thus the two combined instruments show, firstly, the depth, and,
secondly and independently, the quality or kind of bottom, and thus indicate the
position of the ship.
As it is possible that at great depths the water may have such power for
absorbing air as to make this apparatus inapplicable I may find it necessary to use
an intermediate fluid, such as mercury or oil, and instead of having a plain tube
employ a syphon or reservoir tube so as to keep the air permanently separate from
the water.
The line I propose to adopt for the purpose is either steel wire or cat gut. The
former I propose to preserve from rusting by fixing a wiper or greaser to the drum
or stand on which the wire is coiled, and when I use the latter I propose to keep
it well coated with a powder that keeps off water, and in a dry place when not in
use.
Instead of one tube inside another I may use a transparent tube containing a
floating cork or other light body. This cork or float has a slit or groove on its side
and is driven up the tube by the pressure of the water, thus recording the depth of
water on a scale. The slit or groove allows the air above it to escape without
forcing it down.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Bassnett in the Great Seal Patent Office on the 9th
December 1879.
THOMAS BASSNETT, of Liverpool, in the County of Lancaster.
"IMPROVEMENTS
IN APPARATUS FOR TAKING SOUNDINGS FOR NAVIGATING AND OTHER PURPOSES."
The object of this Invention is to secure correct soundings without the slackening
of the speed of the ship frequently requisite with the somewhat defective and very
expensive apparatus at present in use.
The principle of my Invention consists in causing water or any intermediate
liquid to be forced into an air chamber by the pressure of the sea water at great
depths, compressing the air into a smaller volume, that volume being exactly
commensurate in inverse geometric ratio to the pressure. The water or other liquid
once forced to overflow into the air chamber remains at the bottom of the air
chamber, and can be measured at leisure after the apparatus has been withdrawn
from the sea, and in this way the exact amount of compression and consequently
the pressure at the greatest depth can be read off on a scale, or the volume of water
that has overflowed into the chamber can be measured,

page_text: The form of apparatus that I at present prefor is shown in the accompanying
Drawings, and is the same as that already in use by a large number of the principal
lines of steamers sailing out of the port of Liverpool. In these Fig. 1 is an
elevation of any apparatus; Fig. 2, sectional elevation; Fig. 3, sectional plan of
same; Fig. 4, view of cone for raising deposit from the bottom. A is a vertical
parallel brass or copper tube with open ends of small internal bore, so that no
allowance need be made for the extra amount of air contained in this tube; its
lower end is in communication with the wator to be sounded. The upper opens
into a chamber consisting of a Bohemian glass tube B; this tube is hermetically
closed at top by india rubber or other plastic or elastic washer or packing C and
cock D hereafter described. The tube can extend the entire length of the inner
tube, but I prefer to stop it off at a point about three quarters of the way down,
leaving an opening to flow into an enlarged chamber E near the bottom, as shown.
By this moans the space at the bottom into which first water flows is much
increased, so that instead of the water overflowing with the first five and one half
fathoms or thirty three feet occupying nearly half the tube, it only occupies the
chamber, and a very much longer portion of the tube can be used for scale; a taper
can also be used to make the scale of equal parts from five and one half
fathoms to any point; carrying the principle further, for great depths a tapering
glass tube can be used, so that the graduations on the upper end can be further
apart than would otherwise be the case. This chamber E is hermetically closed
except where it opens into the tubo B. The cock D could, if desirable, be placed
opening into this lower chamber instead of at the top, but it would be more in the
way in sounding. G is the metal case or sinker enclosing the apparatus, of which
case however chamber E forms a part. This case should be as small in diameter
and as smooth as possible, so as to cause the minimum amount of resistance to its
passage through the water. The case G serves not merely as a sinker but also as a
protector to the glass. In practice I generally use the usual leaden weight to sink
the apparatus more rapidly, but sometimes use an outer heavy metal case M instead,
which also acts as a protection to the instrument. H, H, are two eye rings soldered
to the case for attaching the line to by means of spring clips I, I, but when used
with iron tube for sinker these are not required. Sometimes I enclose the apparatus
in a very heavy sinker with a hinged lid at bottom of solid metal containing a
valve that will freely admit water and sand, mud, or gravel that the apparatus
strikes against, said valve closing automatically; but for ordinary purposes I prefer
the apparatus shown in the Drawing, Fig. 4, in which J is a cone attached to
case G by spindle K; L, L, L, are three indiarubber or leather washers sliding
loosely on K. When the cone J strikes loose material it sinks in the material and
fills in pushing the washers up. When, however, the apparatus is drawn up the
washers L are forced over the cone mouth by the force of the water, thus preserving
the contents from being washed out till examined on ship board by the operator.
It will be seen at once that instead of two tubes, one inside the other, a single
syphon or double syphon could be employed, and in the latter case an intermediate
liquid could be used, but I do not see any advantage in these modifications, and
only mention them as clumsy infringements that might possibly be otherwise taken
advantage of by persons not grasping the real scope of my Invention.
The cock DI alluded to above can be of any convenient pattern. I prefer
however as simplest the four way cock shown in the Drawing, in which a is the
waterway; b, body of the tap which turns on the taper plug c; d is a washer
which, coming in contact with pin e, prevents b being turned too far in either
direction; f, nut.
The mode of action is as follows:-The line being attached by means of its
spring clips I, I, to eyes H, H, the weight is attached, the cock D turned off, and
the apparatus with sufficient length of line thrown overboard; as it descends the
water rises in tube A, overflows into tube B; on reaching the bottom the cone J
forces itself into the sand or silt, the latter overflows into the cone and fills it.
The water in the meantime has compressed the air in B to the hydrostatic pressure

page_text: surrounding it and filled the spare space; as the apparatus rises the washers sink
and cover the cone, protecting the contents. The air expands the tube B to ordinary
atmospheric pressure on reaching the surface and drives the water out of tube A,
but is without action on the water that has overflowed into chamber E and tube B.
When the apparatus reaches the deck the depth in fathoms is read off on the scale,
the cock D turned to drain off the water, and the apparatus ready for another
sounding.
Having now described my Invention, and the best mode known to me of carrying
it into effect, I wish it to be understood that I do not claim as my Invention
broadly the principle of sounding by noting the amount of compression of a given
quantity of air, as this as been done with more or less accuracy before; but that
which I believe to be new and desire to protect under the hereinbefore in part
recited Letters Patent is,-
1st. The manufacture of sounding apparatus in which the depth of water is
ascertained by measuring or determining the quantity of liquid caused by the
bydrostatic pressure to flow over into a chamber closed air tight except where the
said liquid overflows into it, substantially as described.
2nd. The apparatus for sounding the depth of water, substantially as herein
described, consisting of a tube or its mechanical equivalent opened at one end to
the water to be sounded, and at the other end to a chamber otherwise hermetically
closed, from which the water can be drawn and measured, or in which it can be
gauged before withdrawal.
3rd. The apparatus for collecting specimens of the ocean bed, substantially as
herein described, consisting of a hollow cone, a support, and a protecting washer,
washers, or valves.
4th. The construction of sounding apparatus with a tapering tube for measuring
the height to which the liquid rises, so as to equalize or more nearly equalize the
scale.
In witness whereof, I, the said Thomas Bassnett, have hereunto set my hand
and seal, this Eighth day of December, in the year of our Lord One thousand
eight hundred and seventy nine.
Witness,
CHARLES SOUTHALL,
Clerk to
Wm. P. Thompson & Co.,
Patent Agents,
6, Lord Street,
Liverpool,
and
323, High Holborn,
London.
THOMAS BASSNETT. (L.S.)