THE BOOK OF THE LANTERN. 231 



It will then soon be seen which of the lettered spaces has 

 received the correct exposure ; and a memorandum noting 

 time and distance of lens from screen can either be 

 attached to the negative, or entered in a book against a 

 number corresponding with a number scratched on the 

 glass negative. 



The same principle can be applied to contact printing 

 in a frame on bromide paper, by gas or lamp light. When 

 the frame has been charged with its negative and the 

 bromide paper, support it upright at a distance of, say, 

 18 inches from the turned-down flame. Now, place 

 in front of it an opaque card, sufficiently large to more 

 than cover the frame. This card should have a hole about 

 1 inch in diameter cut in it in one corner. Turn up the 

 light and expose for five seconds. Alter the position of the 

 hole and give ten seconds, and so on. When the paper is 

 subsequently developed the several exposures can be 

 readily identified, and the negative can be labelled to the 

 effect that it requires so much exposure at a given distance 

 from a flame. Thus Bromide paper, 18 in. 25 sec. This 

 negative will then be an infallible guide for the exposure 

 of negatives of a similar 'type; for a systematic worker, 

 unless he be quite a beginner, will fall into the way of 

 producing negatives of much the same character and 

 strength, and printing from them by lamp light will then 

 become an easy matter to him. 



After this somewhat long but not unnecessary digression, 

 I will resume my directions for enlarging on bromide 

 paper, and for the sake of simplicity will suppose that the 

 operator is not supplied with the special form of easel 



