THE PHOTOGRAPHIC IMAGE.* 



By Prof. Raphael Meldola, F. R. S. 



The history of a discovery which has been developed to such a 

 remarkable degree of perfection as photography has naturally been a 

 fruitful source of discussion among those who interest themselves in 

 tracing the progress of science. It is only my presence in this lecture 

 theater, in which the first public discourse on photography was given 

 by Thomas Wedgwood at the beginning of the century, that justifies 

 my treading once again a path which has already been so thoroughly 

 well beaten. If any further justification for trespassing upon the 

 ground of the historian is needed, it will be found in the circumstance 

 that in the autumn of last year there was held a celebration of what 

 was generally regarded as the jubilee of the discovery. This celebra- 

 tion was considered by many to have reference to the public disclosure 

 of the Daguerreotype process, made through the mouth of Arago to the 

 French Academy of Sciences on August 10, 1839. There is no doubt 

 that the introduction of this i^rocess marked a distinct epoch in the 

 history of the art, and gave a great impetus to its subsequent develop- 

 ment. But while giving full recognition to the value of the discovery 

 of Daguerre, we must not allow the work of his predecessors and con- 

 temporaries in the same field to sink into oblivion. After the lapse of 

 half a century we are in a better position to consider fairly the influ- 

 ence of the work of different investigators upon modern photographic 

 processes. 



I have not the least desire on the present occasion to raise the ghosts 

 of dead controversies. In fact, the history of the discovery of pho- 

 tography is one of those subjects which can be dealt with in various 

 ways, according to the meaning assigned to the term. There is ample 

 scope for the display of what Mr. Herbert Spencer calls the " bias of 

 patriotism." If the word " photography" be interpreted literally as 

 writing or Inscribing by light, without any reference to the subsequent 

 permanence of the inscription, then the person who first intentionally 

 caused a design to be imprinted by light upon a photo sensitive com- 

 pound must be regarded as the first photographer. According to Dr. 

 Eder, of Vienna, we must place this experiment to the credit of Johanu 



* Friday evening lecture delivered at the Koyal Institution, on May 16, 1890. 

 (From Nature July 10, 1390, vol. xlii, pp. 246-250.) 



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