Guido Ferrari 



MAKER OF FINE GRADE 



.,/ Optical and 



p lidathematieal 



Instruments 



Experimental Work — 



Models for Patent Office, Etc. 



DRAWING IN5TRUHENT5 A SPECIALTY. 



No. 911 VINE STREET, PHILA., PA., U. S. A. 



OF INTEREST TO ALL STUDENTS AND LOVERS OF NATURE. 



THE OBSERVER 



DEVOTED TO 



All Departments of Nature Studies. 



OUR MOTTO: 

 " Keep Your Eyes Open " 



(To observe the wonders and beauties of Nature. ) 



<^~ Offlci«al Organ of the Agassiz Association. 



Consists of Three Departments: 

 1. The Outdoor World. 2. Agassiz Association. 



Practical Microscopy. 



E. F. BIOELOW, Managing Editor and Publisher, Portland, Conn. 



