So bdivihon of the Ground, of one Hvpothenufe of 600 Feet into 30 Rod L engths , and method of tracing the Line through the iVir by means of the Boning hods 
Fhilos. Trans. Vot.LXXV . Tab. XVIII p . 480 
For tJbe DESCRIPTION and APPLICATION of tie DEAL RODS See. 
inml 
s> 
>3 
74 
~~i — 
V 
/6 
'7 
~~i — 
7 7 
— 1 — • 
<9 
20 feet . 
2 c ? or middle Rod . 
i tt or right-hand Rod. \ 
Hasfre. /c 
