30 THE ILLUSTRATIONS 



students of biology generally and medical 

 students especially. The camera used is un- 

 usually large in order to ensure direct photo- 

 graphy. In no case are the results produced 

 from the enlargement of small negatives. 7 



Subsequently we were invited to exhibit 

 them at the Conversazione of the London 

 University held at the Imperial Institute, 

 May 27. 



When photographs are enlarged from small 

 negatives there is no material gain as regards 

 new details. The advantage of a large camera 

 (Fig. 3) is shown in several of the illustrations 

 where a vast amount of design is visible which 

 could not be secured by ordinary enlargements. 



We are well aware that with the electric 

 light or even the oxy-hydrogen lime-light, 

 time could be saved as regards the exposures; 

 but for general workers it is better to show 

 what can be done with ordinary means of 

 illumination, than to lead them to think that 

 the electric or other light is indispensable. 



The extra large camera is not absolutely 

 necessary in all cases of photo-micrography, 



