Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

218 Molesworth’s pocket-book Railway Cukves. RELATIVE VALUE OF USEFUL ANGLES TC ANGLE OF INTERSECTION- Let x — Half the angle of intersection, then A - 90° - x । D = 90° + x B = 90° - x E + F = 90° - x C = 90° + x | G + H = 90° - x Setting out with Two Theodolites If any two lines be set out from the starting pointe of the crave having the sum of their tangential angles (E + F) = 90° — % ; the intersection of these two lines will be a point in the curve. By a series of such points the whole curve may be set out if the country be sufficiently open to allow of it.