CH. Villi PHOTO-MICROGRAPHY . 207 



Naturally for the vertical camera the light will come from the side and not 

 from a skylight, although good results are obtained with a skylight if one so 

 places the camera that it does not cast objectionable shadows. 



As shown in Figs. 161, 165, the object is placed upon a glass support and 

 the background is quite a distance below the support. For a dark object the 

 background should be light, and for a light one dark. Black velveteen is 

 excellent for a back-ground. The advantage of the glass support is that the 

 shadows in the background which often make it difficult to tell just where the 

 specimen ends and the background begins, are wholly done away with, and 

 that too without at all affecting the proper light and shade of the object itself. 

 (Method of W. E. Rumsey, Canadian Entomologist 1896, p. 84). 



Fig 164. Tripod magnifier as a focusing glass. 



This is carefully focused on a scralc/i or pencil mark 

 on the lower or ground surface of the focusing screen. 



Then whenever the object is sharply focused the focal 

 plane will be at the level of the sensitive surface. 



\ 275. Prints. — If the photographic prints are to be used solely for out- 

 lines, the well-known blue prints so much used in engineering and architecture 

 may be made. If, however, light and shade and fine details are to be brought 

 out with great distinctness, either an aristotype, velox, platinotype or bromide 

 print is preferable. 



§ 276. Recording, Storing and Labeling Negatives. — In 

 order to get the greatest benefit from past experience it is necessary 

 to make the results available by means of a careful record. For 

 this purpose the table (§ 316) has been prepared. If one gives the 

 information called for in this table, whether the result is successful 

 or not, one can after a time work with great exactness, for the 

 elements of success and failure will stand out clearly in the table. 



§ 277. Labeling Negatives.— After a negative is dry the 

 labeling can be done on the gelatin side with carbon ink. 

 Enough data should be given to enable the certain identification of 

 the negative at any future time. 



§ 278. Storing Negatives. — This is satisfactorily done by 

 putting each into an envelope and writing a duplicate label on the 

 upper edge, and then the negatives may be placed in drawers in 



