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Publication numberUS364630 A
Publication typeGrant
Publication dateJun 14, 1887
Publication numberUS 364630 A, US 364630A, US-A-364630, US364630 A, US364630A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 364630 A
Abstract  available in
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Description  (OCR text may contain errors)


No. 364,630. Patsntedfiune 14-, 1887.

Invenhr: "fijendMBar ye r.





SPECIFICATION formingpart of Letters Patent No. 364,630, dated Junel l, 1887.

Application filed August 90, iPiG.

Serial No. 21!, 101; (No model.)

ToaZZ u-hom it may concern: i

Be it known that LJOHN iii. BOWYEInU. S. N., of Erie, in the county ofErie and State of Pennsylvania, have invented new and useful Improvcnients in Distance-lnstruments; and I do hereb l :clare that the followingisafull, clear, and exact description thereof, reference being had to the accompanying d rawi ugs, which form a part of this specification.

This invention relates to new and useful iniprovements in distance-instrnments of that class wherein the distance of an object is det rmined by the angles formed by it with a base-line at two different stations; and the ineipal object of my invention is to devise 1; use on board ship to determine its distance while sailing from any stationary object on shore, such as light-houses, thereby enabling the mariner to easily locate the position of his ship on the chartby the use of this distance and. the angle of observation.

My inventionconsists in the peculiar construction of the instrument, all as hereinafterdescribed, and set forth in the claims.

In the drawings which accompany this specification, l ignre 1 isa perspective view listance-iustrument. Fig. 2 is a cross- -ion on the line x so in Fig. 1. Fig. 3 is a diagram showing its application.

A is a slotted base-plate carrying two disks, P C, the former being stationary and the other 'dingly secured thereon, the slot in the baseate engaging with a tonon on the movable for the purpose of guiding said disk on the base-plate.

D and. E are two legs pivotaliy secured at 0 end in the center of the disks l3 0, res -ectively, by means of the tightening-screws F. The legs D E and the base A are graduated alike and numbered to facilitate the reading. 0 the base-plate the numbers run from the staionary disk toward the movable disk, zero correspondin with the center of the stationary disk, and to permit reading from either side the basepiate has two series of graduations wit-.1 the numbers marked the reverse in relation to each other. Thenunibering of the graduations on each leg begins at the pivotal point and runs toward the point. The graduation is preferably in inches and usual subinstrument of this kind especially adapted divisions, which, in theoperation of the in strunient, are intended to represent miles and fractions thereof.

The disks B O are graduated to indicate degrees or points, and the movable disk is provided with two openings, G, by means of which the distance of the center of the movable disk from the center of the stationary disk may be accurately read on either graduation of the base-plate.

Suitable sights, H H, may be placed near the free ends of the legs, and also at their pivotal points, if desired, as it is necessary in the operation of the instrument to adjust the inner or graduated edge of the legs in line with the ob jest the distance 'of which it is desircdto find.

To permit the disk U to approach tiiedi'sk' B as near as possible, the disks are made to overlap cach-other.

inpractice the instrument is placed on the ship on top of a rail or other suitable elevation, where it can be secured in thelongitudinal direction of the ship and command a free view for sighting objects. Now, supposing the ship, while sailing on its prescribed course, has sighted a light-house, L, from which its distance is desired to be found, the operator takes his first. observation by sighting the leg on the stationarydisk in line with the object, and then clamps it firmly in position by means of the pivotal screw F. Au interval oftinie is now permitted to intervene before proceeding with the operation, the ship being kept meanwhile on astraight course, which is carefully noted, together with the distancein miles the ship is making since the time of the first observation. Suppose an hour has elapsed, in which the ship has sailed, as indicated by a log, the dis tance 0, equal to fourteen miles, the operator then adjusts the movable disk Q on the baseplate A to the graduation-mark 1i, and then, after sighting the leg on the movable disk in line with the light-house, tightens the screw F on the pivotal point of theleg. Now the operation is completed, and the distances MN from the lighthouse to the first and to the second point of observation are directly indicated in miles by the scales on the respective legs at the point of intersection P. v

If the course of the ship during the observation has been noted and the angles of obser I CK vation are read on on the disks, all the factors necessary to lay down the course of the ship on a chart are known. If the latter object is the principal aim sought, the graphical execution on the chart is greatly facilitated by the use of asimilar instrument to theone described,

. on which the scales correspondwith the scale on which the map is drawn, the manner of using such second instrument being self-evident.

My improved instrument is based on the well-known relation of proportional triangles,

and it will easily be seen that by the use of my instrument on board ship, which permits the .convenient use of a long base-line,1nore accuratti -esults may be obtained than by the usual means at present employed, While at the same time its operation is so simple that its use does not require any special training, but can be put in the hands of any sailor.

My instrument may be also used on land to I advantage whenever the use of a long baselineis at all convenient or made necessary by other circumstances.

I preferably cover all or portions of the legs with luminous paint to permit sighting an'object in the. dark; but such paint may be used tion of the slotted base A, graduated upon both sides of said slot, the graduated stationary disk B, the graduated sliding disk 0, having a tenon engaging into the slot ofthe base A, the graduat-ed'legs D E; pivotally secured to the center of the disks B C, respectively, and the clamp-screws F, all substantially as described.

3. The combination, with the base A,'having central longitudinal slot and graduated upon each side of said slot, of the graduated disk 0, movable upon said base and provided with two openings, G, substantially as described, and for the purpose specified.

JOHN M. BOWYER. Witnesses:

HAL M. Honens, H. S. SPRAGUE.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2448410 *Aug 16, 1946Aug 31, 1948Baumgartner WalterCalculating device
US2506785 *Dec 29, 1944May 9, 1950Rca CorpPulse-echo system for indicating angles
US2874475 *May 8, 1953Feb 24, 1959Mcgaffey Edgar WPipe and pipe joint gauge
US4095342 *Jan 10, 1977Jun 20, 1978Oertli Donald ERadio navigation aid
US4712308 *Aug 29, 1986Dec 15, 1987Richmond Jr Carleton RMeasurement method and apparatus
US5404648 *Mar 4, 1994Apr 11, 1995Taylor, Jr.; Ralph A.Navigational plotter
US6134796 *Mar 19, 1998Oct 24, 2000Altech Controls CorporationAircraft navigational plotter
Cooperative ClassificationG01C3/18