8? Inflnmental InfiruBms 



Degrees 30 Minutes: As for D, it being above 

 a Semicircle, ^'i;s. 254 Degrees 30 Minutes, 

 you muft move the Semicircle round on O 'til 

 the Diameter come again on N S : prick off 

 74 Degrees 30 Minutes, Supplement to 254 

 Degrees 30 Minute^;, and draw A, B, 

 © C, D, on which Lines fet off the Qiian- 

 tities noted in the Field-Book, and draw A B, 

 BC, CD, and DA. 



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TofarvejaRoadhythe TheoDoLiTe: 



Fig. laf' ET S C R O and N EF G be 



L# a Road to be furvey'd: Begin at 

 either End, fijppofe A, where place the In- 

 ftrument, the Need{e hanging over the Points 

 of North and South \n the Chart 5 let a Man 

 go as far as you can fee, or the next Bend of 

 the Road, B, and dired your Index to cut 

 him in 11 Degrees 30 Minutes, N W. Mea- 

 fure the Off-fet to the Left, A S, 66 li. ^ and 

 the Off-fet to the Right, A G, 75 h. Mea- 

 fure A B I ch. 90 ii. an Houfe to the Right at 

 A. 



Place the Inftrument at B, in its former 

 Polition ^ let a Maw go to C, another Bend 5 

 cat him with the index in 10 Degrees, N E 3 

 mea&ire BC (the ftationary Diltance) 2 ch. 

 %i li. 5 meafure a Ifo the Off-fet to the Left, 

 Be, 5aii, 5 and to the Right, B F, 85 li. , 



Remove 



