Bearing_compass History_of_the_compass

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bearing compass (18th century)


a bearing compass magnetic compass mounted in such way allows taking of bearings of objects aligning them lubber line of bearing compass. surveyor s compass specialized compass made accurately measure heading of landmarks , measure horizontal angles map making. these in common use 18th century , described in 1728 cyclopaedia. bearing compass steadily reduced in size , weight increase portability, resulting in model carried , operated in 1 hand. in 1885, patent granted hand compass fitted viewing prism , lens enabled user accurately sight heading of geographical landmarks, creating prismatic compass. sighting method means of reflective mirror. first patented in 1902, bézard compass consisted of field compass mirror mounted above it. arrangement enabled user align compass objective while simultaneously viewing bearing in mirror.


in 1928, gunnar tillander, swedish unemployed instrument maker , avid participant in sport of orienteering, invented new style of bearing compass. dissatisfied existing field compasses, required separate protractor in order take bearings map, tillander decided incorporate both instruments single instrument. combined compass protractor built base. design featured metal compass capsule containing magnetic needle orienting marks mounted transparent protractor baseplate lubber line (later called direction of travel indicator). rotating capsule align needle orienting marks, course bearing read @ lubber line. moreover, aligning baseplate course drawn on map – ignoring needle – compass function protractor. tillander took design fellow orienteers björn, alvid, , alvar kjellström, selling basic compasses, , 4 men modified tillander s design. in december 1932, silva company formed tillander , 3 kjellström brothers, , company began manufacturing , selling silva orienteering compass swedish orienteers, outdoorsmen, , army officers.








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