A New Topography Method. 21 1 



which the same men were able to produce after warmer weather 

 came. The work was carried on regardless of weather and 

 atmospheric conditions, in severe cold, accompanied by high 

 winds, in snow and fog. The hand level froze up, the mirror 

 became clouded, the level man's fingers so cold he could scarcely 

 turn the thumbscrew, and with nothing like the refinement of 

 touch that became possible with warm weather. The results ob- 

 tained under the conditions mentioned above, varied — the errors 

 running between about 17 feet for distance under i^ miles to 200 

 feet for distances up to 4^ miles. Later, in warm weather the 

 same men were able to run levels over circuits of from i^ to 6 

 miles with errors ranging from i foot to 23 feet. A very large 

 amount of the work was done over extremely broken country 

 with errors under 10 feet for an average distance of 3 miles- 

 This work is close enough for a survey of any nature. It might 

 be said that the work could scarcely be of sufficient accuracy to 

 warrant conducting it under such severe conditions as prevailed 

 on the job during last winter, while in good weather the work is 

 easily done and produces very satisfactory results. During the 

 severe weather of winter, not only was the quality of level work, 

 seriously afifected, but the quantity of work was at a minimum. 

 At no time was there enough snow to make snowshoeing practic- 

 able, while it was deep enough to make travel very laborious. 

 Thick beech and chestnut brush became laden with snow and 

 formed as much of an impediment to compass work, as thick 

 leaves. The laurel and rhododendron patches, always a serious 

 problem, were rendered even more difficult to traverse. Under 

 these conditions a mile a day was considered a good days work, 

 while a mile and a half was the maximum. With the melting of 

 the snow the amount of work and quality were both increased, a 

 maximum days work being three miles. After the leaves came 

 out, it became necessary to put on an extra man to clear away the 

 brush, which resulted in another increase in the amount of work 

 done, the average being 3f miles with a maximum or 4^. Of 

 course a certain amount of the increase was due to greater 

 familiarity with their work on the part of the men. At all times 

 the chain crew was able to keep up with the compass crew so 

 that it is entirely probable that even 5 miles might be possible, 

 even in such broken country as West Virginia. 



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