|Q^ SURVEYING WITHOUT INSTRUMENTS. 



Nautcalfurvey- Stick a pin through the paper firm into the board, at the 



jng withoi 

 ftruroents 



jng without in- p art meant to reprefent the ftation A, and lay a ruler with a 



perfect ftraight edge on the paper, touching the pin at A and 

 pointing towards the ftation B, and draw the lineAB: in 

 like manner draw lines from A towards all the points, rocks, 

 bays, &c. numbering the lines as the points, rocks, bays, &c. 

 are numbered in the eye-fketch : Proceed next to the ftation 

 B, and place the board horizontally before you, fo that the 

 line A B fhall point back towards A, and fecure the board 

 with the fame precaution as at A, to prevent its fhifting : then, 

 in the line A B, ftick a pin firm through the paper into the 

 board, in that part meant to reprefent the fiation B ; from 

 which point draw lines pointing towards the different points, 

 rocks, &c. as was done from A, numbering them in like 

 manner. Now, where the lines drawn from B interfeft thofe 

 of the lame number drawn from A, will be the place of the 

 points, rocks, &c. to which the lines were directed to from 

 the ftations. Sketch in the fliore between the points, &c. 

 and the plan is completed. 



The meridian-line may be found by compafs, or more cor- 

 rectly, by drawing the line of the fun's bearing from one of 

 the ftations, and taking his altitude at the fame time. Then 

 with (he latitude, altitude, and declination, compute the azi- 

 muth, and lay it off to the left or right of the line of the fun's 

 bearing, according as the fun was to the right or left of the 

 meridian, and it will give the true north and fouth, or meri- 

 dian-line. 



If the diftance between any two points on the fliore be 

 meafured, it will give you a fcale for the plan ; but it may often 

 be found more convenient to meafure off a bafe, as A C, 

 from one of the ftations, in a direction nearly perpendicular to 

 the line A B ; and let it be in length equal to fome part of a 

 geographical mile, as 380 feet = fo or 760 = -§-, or 1520 

 = ^,. or 3040 — \ , or any part of a mile ; then will the line 

 A C be a fcale to the plan. 



I have fuppofed any common board and ruler to illufirate 

 the fimplicity of this method of furveying : but to fuch as are 

 provided with a drawing frame, it will be found convenient 

 to extend the paper on; and if a ruler has fights perpendicular 

 to its edge, it will be found commodious, and require lefs 

 trouble, I hope the eafe and expedition with which the whole 



is 



