The transparent Three-Arm Protractor measures 12-3/16" in diameter and is divided to single degrees with vernier's readable to two arc minutes. The markings are internal, and the clear laminated plastic is .040" thick. The left and right arms, which extend 13-1/2" from the center of the circle, can be rotated a full 360 degrees and clamped at any point. This instrument is used in the same manner as the metal Three-Arm Protractor, Model 24-1175, but for sighting closer objects or where the accuracy of the metal three-arm protractor is not needed. Model 24-2273 is furnished in a special heavy cardboard storage case.

The W-K Precision Three-Arm Metal Protractor, which can be read to single minutes of arc, consists of a 6-1/4" diameter hard bronze circle with one fixed arm and two moveable arms. Each arm has an 18" ruler and a 13-1/2" detachable extension ruler. The circular scale is graduated to half degrees, numbered every 10 degrees. Each arm is provided with a vernier reading to single minutes. The instrument is provided in two models, 24-1175R, with the right moveable arm closing to zero and 24-1175L with the left moveable arm closing to zero. Four interchangeable pivot plugs are provided for determining and marking the location of the instrument center.

Used to determine the position or bearing of an object from a know reference point. Ideal for locating fires, the Forestry Service uses this instrument to help direct fire fighters pin point a fire location in the national forests. The instrument can also be used on ships to locate the position of other ships or objects on shore to determine their location relative to the shore positions. The circle is made of corrosion resistant material and is graduated in single degrees. The "gun-sight" aiming device provides an accurate and easy means to read the bearing angle.

The sextant has a guaranteed accuracy of better than 9 seconds of arc. The frame and the arc are constructed of a special brass alloy and the entire instrument has been treated and enameled to prevent corrosion. The handle is slightly inclined to provide a more natural grip. The mirrors are extra large and are of the finest optical quality, providing a high light intensity. Filters included. The sextants are available with a choice of 4 x 40 or 6 x 30 telescopes. A bubble attachment and astigmatizer lens are available. With case.

Warren-Knight Precision Levels are made of thoroughly seasoned iron alloy, machined and tapped on the bearing surfaces to provide a very reliable and durable instrument. The main vial is precision ground and graduated for consistent accuracy. These levels are also fitted with a cross test vial to prevent the level from being used in a canted position.

The Telescopic Marine Alidade is a navigational instrument used aboard ship for observing distant objects and determining their bearings. Using adapter rings to mount the alidade on a compass or gyrocompass indicator, the Model 13-7500 is primarily intended to be used with the 6-inch and 7-1/2 inch magnetic compass and the 6-inch and 7-1/2 inch gyrocompass indicator. The nitrogen purged main housing consists of a reticle-equipped, terrestrial telescope for viewing distant objects and an auxiliary optical system for viewing the compass card and the bubble in the level vial. Furnished complete with storage case and adapter rings. Mark 6 and Mark 7 Alidades available. We service and repair all makes and models.

The Vertical Plumb Aligner is used to determine the position of points located in the same vertical and plumb plane as the point produced by the intersection of the cross-wires of the aligner's telescope. Among other applications, this unit is used to position circular liquid tank covers over specified graduations or points in the tank floor to insure the correct critical alignment specified. This instrument is not susceptible to problems incurred by using a plumb bob such as movement by wind or setting after being touched. Ideal for applications where accessibility is limited or the distance to the point from the unit exposed is great.

The Binocular Carriage is used aboard ship as well as ground based permanent sighting stations. These carriages provide for smooth and easy movement of the binocular in elevation and azimuth. The elevation control will allow for 70 degrees of rotation, 10 degrees depression to 60 degrees of elevation. It is equipped with a locking mechanism to provide for the securing of the binocular at a desired elevation. The azimuth control will allow for the rotation in the horizontal axis, with a locking mechanism to secure the binoculars at any desired azimuth angle. A graduated circle in 1 degree intervals, is mounted to permit reading the azimuth on a required line of sight. Also provided, is a manually operated mechanism with locking device, which will adjust the height of the binocular through a range of 8 inches. Pedestal base and binocular available.