graves: place of forestry among sciences 41 



(2) Adjust axis W of grinding plate by means of three screws i in the 

 base-plate support (fig. 2). Adjustment is accomplished when a crystal 

 face ground and polished by the wheel is in the position indicated by 

 the telescope. This part of the adjustment usually involves the grind- 

 ing and poUshing of several crystal faces before the correct position is 

 attained, but, as the grinding and polishing of each face takes less than 

 10 minutes' time, the time loss is not serious. 



(d) Adjustment of the axial angle apparatus 



(1) Use glass plate (fig. 3c) so mounted that its edge is parallel to 

 axis P S and is vertical. The correct horizontal position is first ascer- 

 tained by means of telescope and lens combination Bl after which axis 

 P S oi goniometer is turned through 90° to vertical position. 



(2) Place axial angle apparatus (fig. 36) in position and test direction 

 of axes by use of autocollimation at M. Adjust by means of screws C 

 and clamping screw F until axis of telescope is normal to glass plate. 

 Cross-hairs should be vertical and horizontal. Test by rotating glass 

 plate about vertical axis P S and horizontal axis D D. 



(3) Center if necessary by means of mounted glass bead and screws C. 

 Retest adjustment after centering. 



FORESTRY. — The place of forestry among natural sciences.^ 

 Henry S. Graves, Forest Service. 



In an old forest magazine, Sylvan, is a story about Germany's 

 great poet, Karl von Schiller. Schiller, taking rest at Illmenau, 

 Thuringen, met by chance a forester who was preparing a plan 

 of management for the Illmenau forest. A map of the forest was 

 spread out on which the cuttings for the next 220 years were 

 projected and noted with their year number. By its side lay the 

 plan of an ideal coniferous forest which was to have materialized 

 in the year 2050. Attentively and quietly the poet contemplated 

 the telling means of forest organization, and especially the plans 

 for far distant years. He quickly realized, after a short expla- 

 nation, the object of the work and gave vent to his astonishment: 



I had considered you foresters a very common people who did little 

 else than cut down trees and kill game, but you are far from that. You 

 work unknown, unrecompensed, free from the tyranny of egotism, and 

 the fruit of your quiet work ripens for a late posterity. Hero and poet 

 attain vain glory; I would like to be a forester. 



1 Paper delivered before the Washington Academy of Sciences on December 

 3, 1914. 



