The draughtsman's handbook of plan and map drawing, including instructions for the preparation of engineering, architectural, and mechanical drawings (1874)
André, George G · London, Spon · leaf 105
Reference Lines.—In plotting a traverse surveyin which the angles have been measured from a fixed line of direction,the magnetic meridian, the direction of the lines may be all laid downat the first angular point. An example will best show the methodemployed in this case. It is required to lay down… … Set the protractor with its centre accurately placed over this point andits oGOth and 180th divisions coinciding with the meridian. Holdingthe instrument securely in this position, lay off around it all thehearings as entered in the field-hook, numhering them in the order inwhich they were taken.…
Architectural drawing · Cartography
Internet Archive · University of Toronto, Robarts Library · Public Domain Mark 1.0. Free to use for anything.
