Hand compass
A hand compass (also hand bearing compass or sighting compass) is a compact magnetic
The term hand compass is used by some in the forestry and surveying professions to refer to a certain type of hand compass optimized for use in those fields, also known as a forester or cruiser compass.[5][6] A hand compass may also include the various one-hand or 'pocket' versions of the surveyor's or geologist's transit.
History and use
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.
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-damped
By the late 1960s many foresters had begun using more modern liquid-damped compass designs, including mirror-sight protractor models such as the
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.[15] 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.
Marine hand bearing compass
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
Notes
- ^ Frazer, 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
- ^ SCFC, Get Acquainted With Forestry Tools Article
- ISBN 0-07-139303-X, 9780071393034, p. 134: A direct-sighting compass uses a magnifying viewfinder mounted in the compass body to directly view a degreed dial and superimposed indicator line; it therefore differs from a lensatic sight (which uses a simple magnifying lens on a folding arm positioned over the dial), or a prismatic sight (which uses a magnifying optical prism).
- ^ Suunto Oy, The Suunto KB-14 Story, Article Archived 2008-04-09 at the Wayback Machine
- ISBN 0-8166-3661-3, pp. 47-55, 64-72
- ISBN 0-943822-41-6, p. 47: The term cruiser compass derives from the practice of foresters cruising or estimating the value of a stand of timber by taking compass readings to ascertain the size of the stand.
- ^ 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
- ^ Hudson, William J., The Brunton Pocket Transit, 26 January 2005 Article
- 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.
- ^ Rutstrum, pp. 47-55, 64-72
- ^ Bonner Soil & Water Conservation District, Idaho State Forestry Contest (October 2004), p. 25 Article Archived 2008-12-15 at the Wayback Machine
- ^ Nix, Steve, The Best Forestry Field Compass Article Archived 2008-08-07 at the Wayback Machine
- ^ Suunto Oy, The Suunto KB-14 Story
- ^ Rutstrum, pp. 47-55, 197-199
- ^ Rutstrum, p. 72
- ^ Casey, Don, Using a Hand Bearing Compass Article
- ISBN 978-0-07-057131-0, pp. 190-194
- ISBN 978-1-59228-069-8, pp. 91-93
- ^ Seidman, pp. 190-194
- ^ Dickison, pp. 91-93
- ^ Suunto Oy, The Suunto KB-14 Story
- ^ Dickison, pp. 91-93
- ^ Dickison, pp. 91-93
- ^ Suunto Oy, The Suunto KB-14 Story
References
- 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