192 A MANUAL FOR NORTHERN WOODSMEN 



this so that their eyes are true, but with the best of men 

 an occasional swing-off of the chain is necessary. Defects 

 in timber also remain to be allowed for. 



As applied to large tracts the strip system may either 

 be employed within types the boundaries of which have 

 been ascertained, as was explained in the last article, or 

 it may be laid out in long lines across country and itself 

 be used to define those boundaries and to get the topog- 

 raphy. A number of townships in Maine have been 

 surveyed in the following manner: 



a. Township lines re-run and re-blazed ; chainage marks 

 left every half mile. 



b. A center line run through the township, this also 

 being chained and marks left each half mile. ' 



c. From a main camp on the center line, 4-man parties 

 ran strip surveys from a mark on the center line out to 

 the boundary, checked on the mark there, set over a half- 

 mile, and ran back. This was 2 days' work, and the 

 party consequently carried outfit required to stay out one 

 night, the main camp meanwhile being moved along the 

 center line. Note was kept of the ridges and streams 

 crossed, also of the lay of the land, of the bounds of cut- 

 tings, and of marked types of timber. Elevations on such 

 a survey may be got by barometer, and a topographic 

 map made up as a result. 



3. LINE AND PLOT SYSTEM 



A third system employed with some variations in different 

 parts of the country, most largely perhaps among spruce 

 men in the East, combines features from both the fore- 

 going. Under this system the cruiser while at work 

 travels in straight lines through the country to be ex- 

 plored, using his eyes as well as may be while actually 

 traveling, but stopping at regular intervals to count and 

 estimate the trees on an area about him. The area usually 

 chosen is a quarter acre, which has a radius of 59 feet, 

 or, for most men, of 23 paces. For a check on this dis- 

 tance a tape line should always be carried in the pocket, 

 and every morning, as well as occasionally through the 

 day, the eye should be checked by actual measurements. 



