.... General Methods.-The methods employed will depend upon individual choice and the natureof the country. They may be roughly classified according to the observations involved, thus :- (l) Compass bearings and distances, i.e. compass traverse. (2) Azimuth and latitude. (3) A combination of (1) and (2...

... in a point which bears the same relationto each figure. That is, the triple inter- Proceedings.] PIERCE ON THE USE OF THE PLANE-TABLE. 189 section marksthe Etation, andthe board is in meridian." I n other positions in azimuth the linesproduce 6' a triangle of error." I n practice, lines are drawn...

...A BREBNER DIOPTRIC APPARATUS LIGHTHOUSES CONDENSATION AZIMUTH LIGHTS LANTERNS PRISMS RAYS INCLINATION VERTICAL LIGHT ILLUMINATION 386 BREBNERONDIOPTRICAPPARATUS. [Selected (Xtudewts Paper No. 142.) DioptricAppaiatus in Lighthouses capable of producing the required Vertical...

... SPHERICAL AZIMUTH FLASHING FLAMES CATADIOPTRIC METALS MIRRORS CONDENSING RAYS SEA SAFETY NAVIGATION AIDS OPTICAL APPARATUS OF LIGHTHOUSES. 477 May 7, 1867. CHARLES HUTTON GREGORY, Vice-President, in the Chair. The following Candidates were balloted for and duly elected :- HARRYFOOTNEanRd...

...E COWPER © Thomas Telford and ICE 1840 LEVELLING AZIMUTH CAPS TELESCOPES INSTRUMENTS travels. It hastwo axles, one of them fixed andtheother moveable, SO as to accommodate itselftoanyvariationinthewidth between the rails: to the end of the moveable axle is attached an arm, which...