66 INSTRUCTIONS FOR MAKING FOREST SURVEYS, ETC. 



map or obliterating any of its topographic data. Some 

 salient points on the base map should be copied on the 

 tracing cloth so that the two may be registered at any 

 time, for the paper may shrink or the cloth may stretch- 



THE FOREST ATLAS. 



The Forest Atlas at Washington is the central depository 

 for maps, diagrams, statistics, and history of the National 

 Forests and forestry in general throughout the world. 

 Its most important division is that of maps, and the 

 most important maps are those of the National Forests. 



The Forest Atlas now cotnprises 190 volumes, con- 

 taining sheets exactly 18 by 21 inches. They are bound 

 in loose-leaf holders in two ways. Standard binders 

 have the binding margin on the 21-inch side, while town- 

 ship binders have the binding margin on the 18-inch side. 

 No map is made on a sheet less than 18 by 21 inches, 

 and larger maps are made on two or more sheets which 

 are always numbered from west to east beginning at 

 the northwest corner. Borders are omitted. The 

 title consists only of the name of the forest or the 

 number of the township. The top of the map is 

 always north. A binding edge of at least 1J inches is 

 always left blank on the west or left-hand side of each 

 sheet. 



The standard scale of the Forest Atlas is 1 inch to 1 

 mile, and the National Forests have been practically 

 covered by atlas sheets according to this standard. 

 Whenever, in special cases, a larger or smaller scale is 

 necessary for the preparation of any map in the Forest 

 Service, it must sustain the simple relation of X 2 



