ACKNOWLEDGMENT 



is duly made to the following for their kind assistance rendered in the matter of securing 

 photographs for use in this volume: 



Forestry Service, U. S. Dept. of Agriculture Romeyn B. Hough Company 

 Mr. Nathan R. Gra^ ^s J. Horace McFarland Company 



Prof. R. M. Harper Prof. Charles S. Sargent 



