xxiv President's Address for the year 1880. 



keep sensitive for an indefinite period of time if kept in the 

 dark and in a moderately dry atmosphere. The great 

 feature of these films is that they are extremely sensitive to 

 light, and that photographs can be taken with them in one- 

 twentieth or even a thirtieth of the time occupied in the 

 ordinary collodion process. This is an advance which only 

 photographers know the full value of, and it will enable them 

 to obtain practically instantaneous pictures of moving 

 objects on the one hand, and on the other of objects only 

 partially illuminated, such as the interiors of buildings, dark 

 forest scenery , and so forth. Another great advantage they 

 present is that after the picture is chemically impressed 

 upon them by exposure, they remain unchanged, and can be 

 as perfectly developed months after as at the time. This 

 process has not, however, been fully developed in Australia 

 yet, but I hear there is every prospect that it will very soon 

 become familiar to our principal photographers, and replace, 

 as it is rapidly doing in England, the collodion method. In 

 conclusion, I would say a word or two concerning the 

 approaching Melbourne International Exhibition, for it is an 

 occurrence closely connected with the chief objects of this 

 Society. The progress of science and art will there be illus- 

 trated in a far more forcible manner than is possible in any 

 other way, and this Society will be keenly interested in its 

 educational result on the people of the colony. The cost, 

 magnitude, and imoortance of such an undertaking demand 

 that no opportunity shall be missed of ensuring that the 

 utmost possible good to the people shall be secured ; and in 

 order that this may be the case, I am sure you will join me 

 in the hope that while the Commissioners, as in duty bound, 

 will adopt means for obtaining as large a money return as 

 possible, they will not regard this outcome as the only one 

 which is desirable, and that liberal arrangements in the 

 shape of season tickets, low admission days, and such like 

 will be made, in order that the full instructing effect upon 

 the mechanics, artisans, and the youth of our country may 

 remain among us a kind of compound interest for the cost. 



