1903.] OF THE ZOOLOGICAL BIOSCOPE. 335 



important educational factor in my hands. Modern methods of 

 teaching all go to prove the importance of teaching thi-ough the 

 agency of the eye as well as the ear, and it is a matter of common 

 knowledge amongst teachers that a lecture demonstrated by a 

 graphic series of experiments or pictures is much more vividly 

 impressed upon the minds of the students than a simple unillus- 

 trated oration. 



As regards the application of Animated Photography to the 

 Microscope, I was primarily led to attempt it through my inves- 

 tigations into vaiious diseases of plants produced by Bacteria. I 

 felt that the oixlinary method of preparing bacteiia for microscopic 

 examination, — to wit : the fixing of the organisms to the cover-glass 

 by passing the cover-glass through the flame of a spirit-lamp, and 

 then staining (more often than not in heated stain), — gave one 

 anything but an accui-ate idea of the natural appearance of the 

 organisms under examination. It appeared to me that, working 

 on such lines, one might as well take a sheep out of the meadow, 

 roast it whole in front of the fire, dip it into a bath of stain, and 

 then hold it up as a true likeness of what a sheep browsing in a 

 meadow appears like. Also, in lecturing, I felt that it would be a 

 great advantage if I could project on to a screen an " animated 

 photograph " of such subjects as the circulation and rotation of 

 protoplasm, the circulation of the blood, &c. 



Of course, the great difiiculty in seeing living bacteria, with any 

 degi'ee of comfort, is the close aiHnity of their refi-active index to 

 the media in which they are cultivated. However, after some 

 months of experimenting, and trying various optical formulae, I 

 succeeded in finding a combination of lenses which would permit 

 of accurate examination of living, unstained bacteria. The results 

 have been very interesting, and I hope on another occasion to have 

 the pleasure of bringing them before the notice of the Society. 



Increase of teaching and literary work put a stop for a period 

 to my attempting to experiment with Animated Photography in 

 my work ; but I was fortunate enough, some little time back, to join 

 hands with Mr. Charles Urban (of the Charles Urban Trading Co., 

 Ltd.), who has very great experience in Cinematography and is the 

 inventor of the Bioscope. The difficulties that had to be overcome 

 in applying Cinematogr-aphy to Natural Science subjects, particu- 

 larly zoology, and to the microscope, were many, but have now 

 practically been overcome. 



How far I have succeeded in applying Animated Photography 

 to Natural Science, as a means of recording and demonstrating 

 phenomena, you will now have an opportunity of judging for 

 yourselves. I will now project a series of Animated pictures 

 showing the life of the Hive- Bee ; a comparison of the mode of 

 capturing food employed by three reptiles, viz., the Toad, 

 Chamseleon, and Boa Constrictor ; and also some of my Animated 

 Photomicrographs showing the circulation and rotation of pr-oto- 

 plasm in Elodea^ the Freshwater Hydra, &c., ifec. 



