Intelligence and Miscellaneous Articles. 89 



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This increased rapidity is accompanied with an increased sharp- 

 ness and distinctness in the outlines of the objects — an effect which 

 is very advantageous and pleasing, and at the same time rather dif- 

 ficult to account for. 



The shortest time in which I have yet succeeded in impressing an 

 image in the camera obscura has been eight seconds ; but I do not 

 mean to assign this as the precise limit, for it can only be ascertained 

 by more careful and multiplied experiments. 



The production of the image is accompanied with some very ex- 

 traordinary circumstances, to which I will advert in a subsequent 

 letter. These phenomena are extremely curious ; and I have not 

 found in chemical writers any mention of anything similar. 



The image, when obtained, must of course be fixed, otherwise 

 the process would remain imperfect. It might be supposed, d priori, 

 that this fixation would be very difficult, the paper being so sensitive. 

 But it fortunately happens that, in this instance, what seems a rea- 

 sonable inference is not borne out by fact, that new photographs 

 are more easily and perfectly fixed than was the case with the 

 former ones. When fixed, a great many copies may be made from 

 them ; and thus the original view can be multiplied with facility. 



I think that the art has now reached a point which is likely to 

 make it extensively useful. How many travellers are almost ignorant 

 of drawing, and either attempt nothing, or bring home rude unin 

 telligible sketches ! They may now fill their portfolios with ac- 

 curate views, without much expenditure of time or trouble ; and 

 even the accomplished artist will call in sometimes this auxiliary aid, 

 when pressed for time in sketching a building or a landscape, or 

 when wearied with the multiplicity of its minute details. 



One of the most important applications of the new process, and 

 most likely to prove generally interesting, is, undoubtedly, the taking 

 of portraits. I made trial of it last October, and found that the ex- 

 periment readily succeeded. Half a minute appeared to be sufficient in 

 sunshine, and four or five minutes when a person was seated in the 

 shade, but in the open air. After a few portraits had been made, 

 enough to show that it could be done without difficulty, the experi- 

 ments were adjourned to a more favourable season. 



Several photographic processes being now known, which are ma- 

 terially different from each other, I consider it to be absolutely ne- 

 cessary to distinguish them by different names, in the same way that 

 we distinguish different styles of painting or engraving. Photo- 

 graphs executed on a silver plate have received, and will no doubt 

 retain, the name of Daguerreotype. The new kind of photographs, 

 which are the subject of this letter, I propose to distinguish by the 

 name of Calotype ; a term which, I hope, when they become known, 

 will not be found to have been misapplied. 



I remember it was said by many persons, at the time when pho- 

 togenic drawing was first spoken of, that it was likely to prove in- 

 jurious to art, as substituting mere mechanical labour in lieu of ta- 

 lent and experience. Now, so far from this being the case, I find 

 that in this, as in most other things, there is ample room for the ex- 



