The Profile Alidade 441 



topography made on the strip line, but a better arrangement is 

 to have two parallel base lines, one for topography and one for 

 the profile. 



The profile alidade has not been used in field work, but test 

 lines were run around several areas to determine how closely the 

 elevations would check. The results justify the belief that this 

 instrument will be exceedingly useful because it records the data 

 directly on the map sheet, and saves eye strain, and also because 

 it promises greater speed and accuracy than the Abney hand level. 



