THE HOSE-LEVEL 



171 



-H 



2. Be careful to have the 

 zero at the same height on 

 both rods (see Fig. 72) ; 



3. Have the two scales 

 on the long rod meet at the 

 zero mark, and the edge of 

 one scale in line with the 

 similar edge of the other. 



223. System of reading. 

 - It is not easy to buy 

 rules or scales graduated to 

 tenths and hundredths of 

 feet, and while these can 

 be procured, they are ex- 

 pensive. Most persons pre- 

 fer to use scales graduated 

 to inches, quarters, eighths, 

 and sixteenths. Indeed, 

 some of the standard level- 

 ing rods are so graduated. 

 The decimal graduations 

 are easiest handled after 

 one becomes acquainted 

 with them. For the con- 

 venience of persons desiring 

 to use the hose-level with 

 decimal reading, Table 

 XVII has been prepared. 

 By reference to the table, 

 any reading in inches, 

 eighths, and sixteenths can 



FIG. 72. Detailed drawing of 

 Fig. 71. 



