Weems Protractor

This navigation tool is versatileand can be used to lay off a course or a bearing, measuredistance between any two points, plot a position on achart from a given set of coordinates, or determine the coordinates of a position on a chart. It is an updatedversion of the Breton and Portland Plotters. Pencil andsharpener included. Dims: 15" x 5". 255Weems Protractor

The Original bi-rola™

Features: This rule’s patented vertical and horizontal rolling motion simplifies course and plotting calculations, while the unique radial arm allows you to automatically includecompass corrections in your course plotting. Dims: Length13-7/8", Width 2-5/8", Thickness 1". Wt. 12 oz. ?Patented four-way rolling motion?Roller body has protractor markings and a nauticalmile scale?Radial arm has Loran interpolator scales and 200millimeter rule?Automatic compass corrections?When radial arm and body are used jointly, the bi-rola
™ rule becomes a 440 mm (17") divider(approximately)?A speed/time/distance table is included?Easy to follow instructions ?Packaged in a protective, durable vinyl pouch 155bi-rola
™ Rule Rolling Plotter

P.R. 500 Rolling Plotter

Made with the professional in mind, the P.R. 500 has aconsiderably larger body than the smaller bi-rola™ rule.Built to take rigorous use aboard commercial and blue water vessels, the P.R. 500 provides one of the easiestmethods invented for plotting courses.Dims: Length 19-5/8", Width 3-5/8", Thickness 1-1/4". Wt. 1 lb. 10 oz. Features: ?Patented four-way rolling motion ?Roller body has protractor markings every
1 /
2 degree?1-1/4" magnifying lens for enhancing chart data?Easy to follow instructions ?Packaged in a protective, durable vinyl pouch 220bi-rola
™ Rule P.R. 500 Rolling Plotter

CAP’N PETE’S NAV TIP CAP’N PETE’S NAV TIP To navigate with confidence, use all available resources. Your depthsounder can provide a very good position reference. Watch your chart for depth contours and check your position against them. If you think you should be in 35 feet of water and your sounder is showing 75, ask yourself what might be wrong. Sounder? BOAT GPS? D.R. Plot? It’s easy to take approximate bearings from buoys, points of land, or lighthouses. Sight over your steering compass, then check the chart to verify your position. The pencil is your ultimate fallback navigation instrument. Even thebest modern navigation electronics aren’t foolproof. A good navigator will keep a ded (deduced) reckoning plot, even if only in his or her head, to double check the electronics. If you have kept a plot and periodically made note of your progress on a paper chart, you will have a good starting point in the event your “always faithful” GPS lets you down.

38