. The railroad engineer's practice . an, two Chainmen, two or more Axemen. The axeman who drives the stakes noAV carries tacks, 9 or better, lath nails, with him, and drives one in the plugat the point where the Transitman is to set up. The Tran-sitman uses the vernier entirely, not using the needle, un-less as a check on the tangents. The curves are all run onthe ground, and the stakes which come upon them set withthe transit. The Leveller keeps close up to the Transitman,and constantly reports the heights to the Principal Assist-ant. The tangents are generally fixed by the paper loca-tions,
. The railroad engineer's practice . an, two Chainmen, two or more Axemen. The axeman who drives the stakes noAV carries tacks, 9 or better, lath nails, with him, and drives one in the plugat the point where the Transitman is to set up. The Tran-sitman uses the vernier entirely, not using the needle, un-less as a check on the tangents. The curves are all run onthe ground, and the stakes which come upon them set withthe transit. The Leveller keeps close up to the Transitman,and constantly reports the heights to the Principal Assist-ant. The tangents are generally fixed by the paper loca-tions, and the usual object is to run a given curve from oneend of a tangent, and strike the hill with the point oftangent (P. T.) at a given elevation, viz., that on the paperlocation. Other problems will also often arise. The fol-lowing are the most useful: Problem 1. To change a curve so that it shall come out in aparallel tangent at a given distance from the old tangent, bychanging the radius. (From Haslett & Hackleys Pocket-Book.). To change the curve A B so that it shall come out at C, DC R = R± 1 — COS. I; or otherwise; Degree of curve AC — degree of curve A B ^in which n is the number of 100-feet chords in A B. 8DC T-, n 10 Problem 2. To change the origin of a curve so that it may passthrough a given
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Keywords: ., bo, bookcentury1800, bookdecade1880, bookidrailroadengineer00clee
