160 w. m. graham — the photography of diptera. 



Printing. 



Photographs of msects to be effective should be printed upon a, glossy paper, 

 as when printed upon a rough paper much of the detail is lost. The choice then 

 is between P.O. P. and glossy gaslight paper. 



Gasliglit paper, in my opinion, produces the more effective prints, but the 

 makers of half-tone blocks seem greatly to prefer prints on P.O. P. for use in 

 block-making. I have found glossy Gravura gaslight paper most suitable for 

 these prints, as this paper permits the use of a dilute Farmer's K-educer after 

 development to improve contrast and to remove friction marks. 



I have found Ilford P.O. P. (white) most suitable for use in the tropics, as it 

 resists the injurious action of solutions above 80' F. better than other papers 1 

 have tried for this purpose. 



