The Montgomery advertiser., 1903-12-27

distance of che black and white pole ac- cording to the angle of his instrument and the number of alternate spaces be- tween two parallel lines running horizon tally across his field of vision. Under the telescope and in the same perpendicular plane is Q ruler and by following this ruler . number of there's corresponding to the exact distance of the pole he can mark on his white ocean a spot core" spondingiy exactly with the spot at which his fellow surveyor has started the con tour map.
 As the man with the pole. who might ba taken for Q perambulating barber, but who is virtually the ocean by proxy, moves 6rom one place to another in the distance the man at the drawing board Is thus able to locate each place at which he stops by Q pencil mark on the growing contour map. What the man with the pole'ts doing Is actually marking series of nIaceg where the edge of the water would be at mean half tide and what the man at the drawing board is doing is reg iatering, on whatever scale ho has de- cided to make his msge. theae same stops on his piece of paper. Now when line is drawn running irfeEuiarly through all these dots and taking into consideration the character oS tho country which they cover, the result is Q 1agGed outline that represents that portion of the base or our hill as t would look # the ocean had converted it into an Island. The student. of course, has to locate many such spots to make his map, even in such simple problem aa oug hill would represent to practicing surveyor The expert topog- rapher, on the other hand, becomes so skilled in filling in c contour that his work requires the exact data for only q few salient points and would nevertheless stand the test of the pole. telescope and horizontal ruler at practically every point in the outline. The same process re- peated from . point ten feet higher gives the outline if the tide had risen another ten feet, and so on until the summit Ot the hill has almost vanished. Tue com. bined results of this curious series or Jagged outlines, unintelligible aa 1t might appear to the average citizen. produces much the same effect to the eyes of Q surveyor as would a birds eye view of the hill, or a downward glance from balloon suspended directly over 1t. If he wishes to run road across any part of the territory he can reduce the contour map In a few moments to what is called a "profile map" of the exact portion which he wishes to traverse, this map showing the high points that must be cut away and the low places that must be filled in to make his road easy and practicable.
 In actual service the surveyor would seldom go any further than the drawing of kis map but the "rech" student. for the completion of his knowledge, must usually reproduce the contour in paste board model. The making of these mod- els is comparatively simple, the thickness of the pasteboard representing each advance of the imaginary tide and each success sive contour being superimposed upon the one preceding. Such a model looks m miniature very much like an original plan upon which nature has yet to build up her decoration of trees and shrubbery and humanity to erect it's houses, fences fac- tories and public buildings.