44 FOEEST EESEEVE MANUAL. 



In reserves containing great areas of unsurveyed timber 

 land it is necessary, in order to prevent multiplicity and con- 

 fusion in the number of districts, to combine these into still 

 larger areas, called divisions. These have been determined 

 and numbered by the central office, and each supervisor will 

 be furnished with a map of. his reserve, showing their out- 

 lines. All applications, reports, and other correspondence 

 referring to timber on land not legally subdivided into town- 

 ships and sections, therefore, must mention division, district, 

 and block by initial, as Div. 3, D-1, B-6. 



The district and division are merely combinations of blocks, 

 and will never be described or estimated as a whole. The 

 block constitutes the unit of measurement, and must be 

 mapped, estimated, and described accurately, for this infor- 

 mation will guide the central office in approving or rejecting 

 applications of all kinds. * 



In surveyed land each quarter section constitutes a block, 

 and the only surveying required will be the occasional reblaz- 

 ing of obliterated section lines, remarking of corners, and 

 division into quarter sections by blazed lines from quarter 

 post to quarter post. In the center of the section should be 

 set a post having the side toward each quarter faced and 

 marked with the number of the quarter, as NE. i sec. 2. 



These quarter sections, while considered as blocks, will be 

 described by land-survey nomenclature, as NE. i sec. 2, 

 T. 3 N., R. 6 W., etc. (See sample map, fig. 1.) 



In unsurveyed land the blocks need not be of uniform shape 

 or size, although, as a rule, they should not contain more than 

 160 acres. They should conform to the lay of the land and 

 the conditions which regulate cutting. Ridges, roads, and 

 streams should form boundaries wherever practicable, and at 

 least one boundary or corner should be identified with some 

 easily-found natural object. Boundary lines need not run 

 north and south or east and west, but may take such angles as 

 are necessary in order to follow the natural outlines referred 

 to. It is desirable to avoid including in one block greatly 

 differing classes of timber or timber which, by reason of ridges 

 or canyons, will not have the same outlet. 



Squads of four men, consisting of compassman, two chain- 



