Precise Levelling of Kinetheodolites: Errors Due to Flexure of the Azimuth Bearing Ring

摘要

The form of the azimuth bearing of the Askania type of kinetheodolite has been found to give rise in many instruments to a complex motion of the mean plane of the alidade. The resulting errors when the instrument is levelled in the prescribed manner are analysed and a levelling procedure proposed, designed to minimise the error.