Hand compass

File:Brunton.JPG

While small portable compasses fitted with mechanical sighting devices have existed for a few hundred years, the first one-hand compass with a sighting device appeared around 1885.Frazor, Persifor, A Convenient Device to be Applied to the Hand Compass, Proceedings of the American Philosophical Society, Vol. 22, No. 118 (Mar., 1885), p. 216 These soon evolved into more elaborate and specialized models such as the Brunton Pocket Transit patented in 1894.Hudson, William J., The Brunton Pocket Transit, 26 January 2005 [http://brunton.williamjhudson.net/ Article] {{Webarchive|url=https://web.archive.org/web/20081208002137/http://brunton.williamjhudson.net/ |date=2008-12-08 }} Hand compasses were soon widely employed in the practice of forestry, geology, archaeology, speleology, preliminary cartography and land surveying.

File:Stratum compass-clar hg.jpg

In the United States, the hand compass became very popular among foresters seeking a compass to plot and estimate stands of timber. While the Pocket Transit was more than adequate for such work, it was relatively expensive. Consequently, a new type of hand compass was introduced: the forester or cruiser compass. Traditionally, cruiser compasses featured a sighting notch, a mechanically-dampedMooers Jr., Robert L. Finding Your Way In The Outdoors, Outdoor Life Press (1972), {{ISBN|0-943822-41-6}}, pp. 48-49: Most of the traditional designs used a momentary button lock mechanism that froze the needle in position to stop excessive swing and permit a reading. or "dry" needle, adjustable declination and a large dial marked in individual degrees using counterclockwise calibration (reversed east and west positions). A screw base for a tripod or jacob staff (monopod) was often fitted as well.Rutstrum, pp. 47-55, 64-72

By the late 1960s many foresters had begun using more modern liquid-damped compass designs, including mirror-sight protractor models such as the Silva Type 15 Ranger or the Suunto MC-1 (later, the MC-2). These compasses were fast to use, particularly along straight cruise lines and were sufficiently accurate for most forestry applications.Bonner Soil & Water Conservation District, Idaho State Forestry Contest (October 2004), p. 25 [http://www.idl.idaho.gov/Bureau/ForestAssist/forestry_2005_contest/forestry_contest_manual_04.pdf Article] {{webarchive|url=https://web.archive.org/web/20081215235309/http://www.idl.idaho.gov/bureau/ForestAssist/forestry_2005_contest/forestry_contest_manual_04.pdf |date=2008-12-15 }} On the other hand, geologists, speleologists, archaeologists, ornithologists, and foresters engaged in precision survey work often used direct-reading models such as the Suunto KB-14, prismatic compasses such as Suunto KB-77 or the traditional Brunton Pocket Transit.Nix, Steve, The Best Forestry Field Compass [http://forestry.about.com/od/toppicks/tp/compass_fav.htm Article] {{Webarchive|url=https://web.archive.org/web/20080807174409/http://forestry.about.com/od/toppicks/tp/compass_fav.htm |date=2008-08-07 }}Suunto Oy, The Suunto KB-14 Story Many models featured an optional quadrant (0-90-0 degree) scale instead of an azimuthal (0-360 degree) system.Rutstrum, pp. 47-55, 197-199

By using a hand compass in combination with aerial photographs and maps a person can determine his/her location in the field, determine direction to landmarks or destinations, estimate distance, estimate area, and find points of interest (marked boundary lines, USGS marker, plot centers). For increased accuracy, many professional hand compasses continue to be fitted with tripod mounts.Rutstrum, p. 72 While the hand compass continues to be widely employed in such work, it has been increasingly supplanted in recent years by use of the GPS, or Global Positioning System receiver.

{{VT|Bearing compass}}

File:Boussole prisme groupe.jpg

The marine hand compass, or hand bearing compass|hand-bearing compass as it is termed in nautical use, has been used by small-boat or inshore sailors since at least the 1920s to keep a running course or to record precise bearings to landmarks on shore in order to determine position via the resection technique.Casey, Don, Using a Hand Bearing Compass [http://www.boatus.com/boattech/casey/27.htm Article]Seidman, David, The Complete Sailor: Learning the Art of Sailing, McGraw-Hill Professional (1995), {{ISBN|0-07-057131-7}}, {{ISBN|978-0-07-057131-0}}, pp. 190-194 Instead of a magnetized needle or disc, most hand bearing compasses feature liquid damping with a floating card design (a magnetized, degreed float or dial atop a jeweled pivot bearing).Dickison, Dan, Powerboat Reports Guide to Powerboat Gear: Take the Guesswork Out of Gear Buying, Globe Pequot Press (2006), {{ISBN|1-59228-069-2}}, {{ISBN|978-1-59228-069-8}}, pp. 91-93 Equipped with a viewing prism, the hand bearing compass allows instant reading of forward bearings from the user to an object or vessel, and some provide the reciprocal bearing as well.Seidman, pp. 190-194Dickison, pp. 91-93 Modern examples of marine hand bearing compasses include the Suunto KB-14 and KB-77, and the Plastimo Iris 50.Suunto Oy, The Suunto KB-14 StoryDickison, pp. 91-93 These compasses frequently have battery-illuminated or photoluminescent degree dials for use in low light or darkness.Dickison, pp. 91-93Suunto Oy, The Suunto KB-14 Story

{{Reflist}}

• Avery, T.E., Burkhart, H.E., Forest Measurements, 5th ed. New York:McGraw-Hill (2002)
• Johnson, Mark, The Ultimate Desert Handbook: A Manual for Desert Hikers, Campers, and Travelers, McGraw-Hill Professional (2003), {{ISBN|0-07-139303-X}}, 9780071393034
• Mooers Jr., Robert L. Finding Your Way In The Outdoors, Outdoor Life Press (1972), {{ISBN|0-943822-41-6}}
• Rutstrum, The Wilderness Route Finder, University of Minnesota Press (2000), {{ISBN|0-8166-3661-3}}

{{Orienteering|type=collapsed}}

{{Forestry tools}}

Category:Forest modelling

Category:Navigational equipment

Category:Hiking equipment

Category:Orientation (geometry)

Category:Measuring instruments

Category:Orienteering

Category:Forestry tools