CHAPTER VII 



PHOTOGRAPHING EMBRYOS AND SMALL ANIMALS; PHOTO- 

 GRAPHIC ENLARGEMENTS; PHOTOGRAPHING WITH THE 

 MICROSCOPE 



§ 325. Apparatus and material for Chapter VII. — 



i. Photographic cameras, hori- 

 zontal and vertical (§ 327-328). 



2. Focusing stand for vertical 

 camera (§ 333). 



3. Focusing glass (§ 334). 



4. Objectives for photographing 

 embryos (§ 335). 



5. Negative records (§ 337, 358). 



6. Photo-micrographic camera 



(§ 338, 34°)- 



7. Microscope oculars and objec- 

 tives (§ 342, 343, 355). 



8. Daylight lantern and other 

 lights (§ 345, 373-374)- 



9. Stage micrometer (§ 350). 



10. Projection apparatus (§ 359- 



363) 



, 11. Photographic chemicals 



(§ 377)- 



12. Plates and printing paper 

 (§ 362, 379-380). 



13. Color screens (§ 366-368). 



14. Microspectroscope (§ 371). 



15. Dark-room light (§ 378). 



16. Printing frames (§ 362-363). 



Photography 



§ 326. From the beginning of the art of photography scientific 

 men have used it to paint for them the forms in nature and the com- 

 plex structures found in the physical and the biological world; and 

 it has been so good a servant that it is more and more called into 

 requisition to delineate all the phenomena as well as the forms of 

 nature and art. This is especially true now that successful methods 

 of color photography have become available. 



§ 327. Photography with a horizontal camera. — The most con- 

 venient position for the camera obscura is the horizontal one (fig. 

 108) and for most of the photography actually done it is very easy 

 to arrange the objects to be photographed in a vertical position; 

 but for much of the photography of science it is very convenient to use 

 a vertical camera, leaving the objects in a horizontal position. With 

 objects in liquids this is a practical necessity. 



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