US40028A - Improvement in instruments for taking soundings - Google Patents

Description

- UNITED STATES` PATENT fOEEIcE.

JOHN ERICSSON, OF NEW YORK, N.

IMPROVEMENT IN INSTRUMENTS FOR TAKING SOUNDINGS.

Specification forming part of Letters Patent No. 40,028, dated September 22, 1863.

To all whom it may concern:

Be it known that I, JOHN ERICSSON, ofthe city, county, and State of New York, have invented a new and Improved Instrument for Taking Soundings; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of l this 'specication The object of this invention is that of taking soundings from vessels navigating shallow waters without stopping or checking the speed of such vessels.

The principle is of a self-acting nature, the depth of water being at all times shown by a self-adjusting index. This remarkable and desirable property of my invention will be fully understood by the following explanation:

It is a well-known fact that there is a certain fixed relation between the pressure and the depth of water, and that therefore if the pressure of the sea at a certain point below the surface be known that pressure accurately indicates the depth. My invention is founded on these physical facts.

I inclose an elastic air-tight bag in a small metallic vessel attached to a tow-line secured to the vessel. An india-rubber tube is connected with the bag by an air-tight joint. This tube is lashed to the said tow-line with its upper end put in communication with an ordinary pressuregage. This pressure-gage I graduate in such a manner that its divisions correspond with the pressure produced by one foot column of water. The index of the gage, therefore, in place of showing, as usual, the number of pounds of pressure to which it is subjected, will show what column of water corresponds with the pressure within the gage. In other words, the index will show how far the instrumentis immersed below the surface of the water. yThus by mere inspection the depth of water'may at all times be accurately ascertained without the inconvenient and inaccurate process of heaving the lead, as hitherto.

In the drawings, Figure l represents a 1ongitudinal section of the elastic bag and the metallic vessel which protects it. et is a bag composed of thin india-rubber, b, cylindrical vessel made of composition metal, open at one end; c, tube made of india-rubber, connected with the air-bag a, and the pressuregage placed on board of the vessel 5 d, tow-line to which the metallic vessel b isattached. This line, which is made fast within the vessel, serves the twofold purpose of towing the bag with its protection and supporting the indiarubber tube.

Fig. 2 represents longitudinal section of forward part of a vessel. b is the metallic protection ofthe air-bag; c, the air-tube, and d the tow-line made fast at a point, e, within the vessel, while the tube c is connected with the pressure-gage f. This latter indicates, as

before described, the height of the column of water above the air-bag. gis an open pipe attached to the forward part of the vessel, through which the tow-line and air-tube are put outboard.

The operation of the instrument will b e readily understood. When put outboard, the weight of the protecting metallic vessel will carry the elastic airbag to the bottom, where it will be acted upon by the pressure ofthe water compressing the air within it until the internal pressure balances the hydrostatic pressure from without. The air-bag being in free communication with the gage on board by means of the india-rubber tube, the pressure will be transmitted to the gage, the index of which will accurately showV the depth Of water at the point where the bag is lodged.

It is an important feature of this instrument that the quantity of air within the bag is not an element affecting the accuracy of the indication. All that is needed is that the volume of air in the bag should be considerably greater than that of the tube. Another marked feature is'the reliability of the indication. For want of air in the bag less depth may be indicated than really is the case; but under no circumstances can the navigator be deceived by an indication of too great a depth.

The most important feature of the invention is, however, that the indication of depth is continuous, as it offers facilities for navigat' ing shallow or unknown waters hitherto unattainable. For ships of war the instrument is indispensable, as it admits of soundings being taken under the enemys fire without exposing the crew.

It is evident that the air-bag may be made of various forms` as also the protecting-vessel which carries it to the bottom. It is also evident that the connection between the bag and the indicator may be made in various Ways, and that the pressure-gage itself may be made of any form whatever as long as it registers the pressure with accuracy. It is, moreover,

evident that the gage With its indicator may be placed anywhere within the vessel or on deck, and that the tow-line and tube may be passed over the raii or through the vesselvs s1 e.

I do not, therefore, confine myself to form or particular arrangement; but

J. ERICSSON.

Witnesses M. M. LIVINGSTON, SAMUEL W. TAYLOR.

Images