76 Germany. 



Paulsen in 1787, Kregting in 1788, mention periodic 

 yield tables; but generally speaking "ocular taxation" 

 or estimating was the rule, checked by experience in 

 actual fellings, the method of the American timber 

 looker. Generally, of course, only the log timber 

 was estimated as with us, and only the very roughest 

 estimating or rather guessing was in vogue until near 

 the end of the period. 



The first attempt at closer measurement was made 

 by Beck'man (1756), who surrounded the area to be 

 measured with twine, drove a colored wooden peg 

 into each tree, one color for each diameter class, when, 

 knowing the original number of pegs that had been 

 taken out, the difference gave the number of trees in 

 each diameter class, and by multiplying the average 

 cubic contents of a measured sample tree in each class 

 by the number in the class its volume was found. 



The method, often employed at present, of ascer- 

 taining by tally the diameter classes on strips forty 

 to fifty paces wide, the so-called strip survey, was 

 described by Zanthier in 1763. 



These measurements were usually confined to 

 sample areas, the use of such being already known 

 in 1739. The contents of the sample area, if a special 

 degree of accuracy was desired, were ascertained by 

 felling the whole and measuring. 



Oettelt, of mathematical fame, was the first to 

 publish something about the determination of the 

 age of trees by counting rings, although the practice 

 probably antedates this account. He knew of the 

 dependence of the ring width on the site and on the 

 density of the stand. 



