THE MICROSCOPE— EARLY HISTORY 



SEVENTY-FIVE YEARS AGO 



Charles A. Spencer and pupil Robert B. Tolles were the 

 pioneer microscope manufacturers of America. Indeed 

 they were prominent among the Scientific Opticians of the 

 world. 



TWENTY-FIVE YEARS AGO 



The Spencer Lens Company was incorporated with the 

 records of these men as its priceless possession and with 

 Herbert R. Spencer, son of Charles A., as its first technical 

 expert. Founded on pioneer research, supported by rare 

 skill in execution, inspired by the highest ideals, this Com- 

 pany has always endeavored to make instruments a little 

 better than those already produced, to set a standard a 

 little higher than that already attained. 



TO-DAY 



During the last quarter century, wonderful changes have 

 transpired in the world of science. The Spencer Lens Com- 

 pany is proud of the part it has played in the progress, 

 proud of the significance its name attaches to a scientific instrument, proud of the fact that 

 its instruments have been recognized as standard by practically every leading educational 

 institution, not only in America but of the world. 



Made in 1850 by Charles A. Spencer 



SPENCER LENS COMPANY 



BUFFALO, N. Y. 



COLORIMETERS 



For The Clinical Laboratory 



Wbt Mill Corporation 



Laboratory Apparatus - Chemicals - Glassware 

 ROCHESTER. N. Y. 



PSYCHOBIOLOGY 



A bi-monthly journal devoted to the field common 

 to Psychology and the Biological Sciences 



Edited by 



KNIGHT DUNLAP 



Johns Hopkins University 



DSYCHOBIOLOGY has been established to facilitate 

 ■*■ the speedy publication of important research in 

 the field of psychobiological inquiry, and also to 

 emphasize the unity and importance of this field by 

 bringing together in one journal material which would 

 otherwise be scattered through the volumes of journals 

 of several different sciences. 



Five dollars a volume — United States and Canada. 

 Five dollars and fifty cents elsewhere. 



Order from WILLIAMS & WILKINS CO. 

 Baltimore, U. S. A. 



— I L 



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