THE PRODUCTION OF POSITIVES, ETC. 149 



daylight; or on glass, if one by lamplight is re- 

 quired. This method has the advantage of allowing 

 the production of any degree of density in the several 

 proofs by subsequent intensification. 



By varying the processes, immense power is given 

 the operator, and no matter what the character and 

 condition of a micro- photographic negative, it is 

 quite possible to change it completely without alter- 

 ing the essentials of the structure depicted on it, 

 thus rendering possible the production of a print 

 from what would otherwise be considered a useless 

 negative. 



It might be objected that the whole process, from 

 the first production of a negative with the micros- 

 cope to the finished print, was too tedious to be 

 practicable. 



This is by no means the case, because the produc- 

 tion of a negative only takes one hour, and several 

 can be produced together with a very little increased 

 expenditure of time. The subsequent washing is not 

 considered, as it requires no special attention. The 

 printing by camera, contact, or enlarging, takes 

 about half an hour, and the finishing about another 

 half hour, therefore from beginning to end the actual 

 time consumed is about two hours. 



