dak * v .,: % f-imm •?■' 
pocket-compass, clinometer, and hand-level. These cross- 
sections show the ground on either side of the line as far as 
desirable by slope and distance, these latter being either meas 
ured by tape or paced. It is evident that contour lines could 
be worked out from these data, but these would not be needed 
if the distances and slopes were well determined, since these 
give a better cross-section than contours alone could do. 
The objections to this method are in the poor means it fur 
nishes for accurate determination of either distances or slopes, 
and the haste with which it is usually done. There can be no 
question but that accurate distances and slopes on cross-sections 
IOO feet apart would give fuller data than even five-foot con 
tours accurately drawn. But to be accurately determined the 
slope would have to change at all points—in other words, it 
would be a curve. As to whether the slopes and distances as 
they would probably be taken would give a better idea of the 
ground than five-foot contours determined by the stadia 
method, and the relative cost of the two systems, are matters 
of experience. Both systems are competent to give a good 
location when they are well executed. 
Note.—The further study of railroad surveying falls within the province of 
the various railroad field-books, which are printed in pocket form ana contain 
the necessary tables for laying out a line of road. Having learned the con 
struction and use of surveying-instruments, and the general methods of topo 
graphical surveying and levelling, the special applications to railroad location 
given in the field-books are readily mastered. They will therefore not bti 
further considered in this work. 
225. 
whatevei 
any bod) 
surveys; 
gation p 
the meat 
slope of 
signals, 1 
locities c 
the same 
ried in s 
ers, Th 
on shore 
as 1 
rately