For paddlers who are on long trips, or who paddle in different parts of the country, marking a rose with true north may be impractical. The Nav-Aid can be marked with two or three north-south, east-west lines using different colors, but the multiple lines can get confusing. There is a double rose on the market by Weems and Plath called the "Compute-a-Course." The bottom part has a grid with a true north rose on it, and the top rose is magnetic. You line up the magnetic rose with the appropriate variation on the true north rose, and you are ready to go. The Compute-a-Course also has a pivoting arrow, but it is easier to use a mile-marked string through the center hole. You don't really need the rose on the lower plastic card; all you need is the grid to align the device on the chart. For any of these protractors, a fast way of getting and reading reciprocals for back bearings is to turn the rose 180 degrees so that it is upside down. For trip planning at a campsite, you may want more accurate tools, or at least ones that let you draw lines. Again, parallel rules and other such devices don't work well in small spaces, and are hard to carry. I favor two 90-degree triangles that are small and flat enough to go into your chart case. A few minutes of practice with them and you'll see how easy it is to move bearing lines between a compass rose and a course. Just align one of the short sides of the triangle on the course and slide the two triangles along their hypotenuses. The triangles don't slide as easily as parallel rulers do, but they are just as accurate. These will work on the bottom of a turned-over kayak or on a cutting board-any small, flat surface. I even used them to take the test for my Coast Guard license. These simple navigation tools can be used in combination with a GPS receiver. Waterproof GPS units are becoming more affordable. Get a waterproof bag for your GPS for additional security, and for flotation if you drop it. Most GPS units will drain batteries in about twelve hours, so you will need to turn it on, acquire the needed information, then turn it off. Be sure to carry spare batteries.

When you first get a GPS, take the time to learn its various functions. After you read the manual, get a book on using a GPS, or take a course. Don't depend on a GPS alone; you still need a boat compass to steer, as the screen is small and hard to read unless you hold it very close. The biggest challenge in GPS use is translating the position indicated in the unit to the chart. You don't want to be plotting latitudes and longitudes while you're sitting in the cockpit. Instead, if you pre-load the centers of the various compass roses on your chart as waypoints, the GPS can give you your bearing and distance from the compass-rose waypoint, so all you need is the scaled piece of string to find your position. Alternatively, call up a waypoint that you have loaded in the GPS and marked on your chart, and use your Nav-Aid or string-equipped protractor to measure bearing and distance from the waypoint. You may find pre-printed waypoints on commercially printed charts. Since the navigators of many larger boats use these waypoints to set their autopilots, the traffic around these points can be high. These waypoints are good things to use to establish your position, but they are bad places to be near at night or in fog. GPS units require that you name your waypoints. Since the GPS can use only a limited number of letters for a name, I often have trouble remembering what name I've assigned to a waypoint. I use a 3" x 5" waterproof notebook to record the names of all of my waypoints, and for other useful navigational data that I might want to have with me in the field. I write down things that are hard to remember, like line-of-sight distances for various eye heights, rules of thumb, formulae and the like. If you aren't using these navigational numbers all of the time, they're easy to forget. In addition to the waterproof notebook, you can use a soft pencil or a grease pencil to write things down on the deck of your boat or on something similar to the white plastic note boards made for sea kayakers or scuba divers. You probably have your own pet tools for kayak navigation-these are some of mine. My criteria: small size-nothing that can't fit into a chart case; low cost-you will probably break or lose things; and, above all, that they work in the small, wet space of the kayak foredeck.

Ben Fuller has been sailing for 40 years and sea kayaking for 20. He is a guide, an ACA instructor and a Coast-Guard-licensed captain living in Cushing, ME.

Resources:

Chart waterproofing solution: Nikwax Map-Proof, (425) 3032410 http://www.nikwax-usa.com Compass roses;

Compute-a-Course Weems and Plath:(410) 263-6700 http://www.weems-plath.com

Magnifier: Handi-Lens by UltraOptix, Inc. (800) 448-2968 or (203) 468-6090 http://www.ultraoptix.com/magnifiers/ fresnellens.html

Small Craft Nav-Aid: Chuck Sutherland 2210 Finland Rd., Green Lane, PA 18054 A 12-page booklet explains its use.

Waterproof charts: International Sailing Supply (800) 423-9026 or (941) 639-7626 http://www.waterproofcharts.com

Maptech:(888) 839-5551 or (978) 933-3000 http://www.maptech.com Maptech's pre-folded charts are easier to read, but the scale is slightly smaller than the ISS charts: They show more area in a smaller space. (Remember that tools have to be calibrated for specific map scales.)

Waterproof ink-jet printer paper: Lat. 26° Inc., (800) 305-0036 http://www.lat26inc.com

Hewlett Packard also makes a waterproof ink-jet paper. Consult with your local paper or office supply outlet.

Waterproof notebooks: Wet Notes, (781) 826-5131 http://www.ritchienavigation.com

Dura-rite: (253) 922-5000 http://www.riteintherain.com

Navigational Tools: Many of the navigational tools mentioned, like the one-arm protractor, are available through major marine hardware stores or online from West Marine: http://www.westmarine.com

Further Reading: GPS Made Easy by Lawrence Letham, Mountaineers Books

The Practical Pilot by Leonard Eyges, International Marine Fundamentals of Kayak Navigation by David Burch,

Globe Pequot Davis Coastwise Piloting Quick Reference (a single plastic 8"x11" sheet) http://www.davisnet.com