DEMONSTRATION 

 RESPIROSCOPE 



An instrument designed by Professor Ganong for proving that plants 

 release carbon dioxide in growth. Complete, as illustrated, $^. 25 • 



One of the new pieces described in the forthcoming new Ganong Appa- 

 ratus catalog which will be sent free on request. 



Bausch ^ Ipmb Optical^p. 



NEW YORK WASHINGTON CHICAGO SAN FRANCISCO 



LONDON riOCHESTEri,N.Y. ^I^ANKFORT 



