U LOCATION. 



The operating value of curvature per degree is assumed at 

 $7 per daily train per annum, but to this should be added the 

 commercial value of lost time, if any, and also all extra con- 

 struction cost of rail-braces, tie-plates, spikes and guard 

 rails. 



Curves exceeding 14 per station should not be used with- 

 out due necessity and usually require both guard and "hold- 

 up" rails for safety. 



A maximum curve, unlike a maximum grade, is not limiting 

 and does not justify the use of similar curvature elsewhere on 

 the same engine district. 



All curves of 3 and over must be provided with terminal 

 transition curves, changing 1 with each chord of 50 ft. On 

 mountain lines this rate of transition may be doubled if 

 necessary. 



Curves less than 300 ft. in length will not be used. 



The minimum tangents between reversing curves must not 

 be less than the chord length of the transition curves; the 

 minimum tangents between curves in the same direction must 

 not be less than 500 ft. 



Curvature on maximum gradients must be compensated at a 

 rate not less than .04 per degree. 



Use standard rules for super-elevation of outer rail. 



RISE AND FALL. 



The effect on operation of minor gradients and small undu- 

 lations, within "velocity limits" is very small, and its capital- 

 ized value is assumed at $2 per ft. per daily train per annum 

 (one way). Limiting curvature and train stops on grades of 

 this kind will greatly increase the cost of operation, and 

 should be avoided in any event. 



The value of rise and fall on grades of considerable rise ex- 

 ceeding velocity limits, but not requiring use of brakes and 

 sand, is $7 per ft. per daily train. 



The value of rise and fall on grades requiring the use ot 

 brakes and sand is $22 per ft. per daily train, and $30 per ft. 

 if on ruling gradients. 



The limiting effect on train weights, of long sections of 

 more or less continuous rise, may considerably exceed that due 



