344 Forestry Quarterly. 



by arbitrary barometer readings is to develope only the mechanical 

 ability of the mapper, and to positively weaken his topographic 

 sense. A completed field sketch made in such a manner will show 

 scarcely a single definite feature. The lines on it merely suggest 

 the form which the draftsman is supposed to develope. It is' 

 practically unintelligible until it has been thoroughly worked over. 

 In this process it usually loses whatever character it m.ay origin- 

 ally have had, and takes on the wooden appearance of the conven- 

 tional map, with long regular curves, contours uniformly spaced 

 and streams all traced in the same pattern. 



Whatever the method of securing the data, the purpose of a 

 finished, contour map is to convey to the user a correct and 

 definite impression of the topography of the country which it 

 covers. It is obvious that no contour can be accurately drawn 

 on the map until it is first developed in the mind of the topo- 

 grapher. Therefore, anything which will give him a better grasp 

 of the details or a more thorough knowledge of their arrange- 

 ment, will tend toward the production of a better map. 



If the mapper can be made to actually see and appreciate the 

 controlling topographic features of an area, the problem of rep- 

 resenting them on the map sheet will ofifer little difficulty. 



The plan of connecting in the field, contours of approxi- 

 mate elevation, is a means toward this end. It is simply the 

 application to strip mapping, of a principle of extensive recon- 

 naissance in which large areas must be mapped from a few points. 

 In such work it is impossible to depend altogether on artificial 

 means for the location of contours, and the topographer is forced 

 to rely to a certain extent upon his eye and his judgment. Ap- 

 plied to strip mapping it does away with the purely mechanical 

 use of the barometer and with the idea that "the draftsman can 

 distribute the error," and it places the responsibility for the ac- 

 curacy of the map squarely upon the topographer. The barometer 

 is used as far as it can be relied upon, but the actual location of 

 many of the contours on the ground is largely a matter of judg- 

 ment. 



The fact that the contours of separate strips must be connected 

 makes it essential that special thought be given to every feature. 

 The lines can not be drawn carelessly, merely as a suggestion to 

 the draftsman of the probable direction of the final contour. They 



