Model C 



Balopticon 



Increase the Lesson's Value 



By giving illustrated talks on history, geography or other 

 subjects you increase by 100% the value of the lesson. You 

 can do this very easily and entertainingly with a 



JJauscli [omk 



Haiopticon 



The Balopticon projects ordinal y lantern slides and can also be arranged 

 to project on the screen, post-cards, photographs, prints, etc.— all in the 

 colors of the original. You will find it much easier to hold the attention 

 of your pupils when you use a Balopticon — and the lesson will be much 

 more forcibly impressed on them. 



Our Model C Balopticon is now priced at $25 and 

 the opaque attachment at $30. 



Write for descriptive circular 8D. 

 Our name, backed b]> half a centum of experience 

 is on all our products — Lenses, Microscopes, Field 

 Glasses, Projection Apparatus, Engineering and other 

 Scientific instruments. % 



Bausch & Ipmb Optical <§. 



■ CW TOftK WASHINGTON CHICAGO SAH fftAKCUCO 



I.OHOOH ROCHESTER. NY. "»*«"<«»?.• 



More about hay and 

 less about mitosis* 



PRACTICAL BOTANY 



Published September 25th. Price, $1.30 



By JOSEPH Y. BERGEN, 



Formerly Instructor in Biology in the English 

 High School, Boston. 



and 



OTIS W. CALDWELL 



Associate Professor of Botany in the University of Chicago 



A new book and fundamentally a practical 

 botany. Its chief purpose is to treat the sub- 

 ject of botany in the simplest manner possible 

 and to treat particularly the portions which 

 will be of most service to those who do not 

 take up the advanced study of the subject. 

 Material is included relating to industrial, 

 agricultural, horticultural and other interests 

 — adapting the book especially to strong pres- 

 ent day tendencies. On finishing the course 

 laid out the student will have acquired a 

 thorough knowledge of the essentials of botany 

 together with a great deal of serviceable infor- 

 mation as to the economio importance of plant 

 life. 



GINN & COMPANY 



Boston New York Chicago London 



Atlanta Dallas Columbus 



San Francisco 



Refracting and Reflecting 



Astronomical Telescopes 



Standard and Portable 



Visual and Photographic 



OBJECTIVES 



Computed by our associate 



DR. F. R. riOULTON 



{Chicago University) 



OBSERVATOR IBS 



Specula, Planes, Eyepieces, etc. 



Photographs and Circulars on request 



LOHflANN BROS. 



Illustration shows 6-in . with pneumatic clock. 



3BKEENVILLE, OHIO 



U. S. Ao 



