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524 THE PHOTOGRAPHIC NEWS. [July 24, 1891. comparisons could be instituted between Draper’s plate and his own. The whole tenor of the paper is philosophi cal, and occupies twelve pages of volume xxii. of the journal already referred to. At the Cork meeting of the British Association in August, 1843, a paper was communicated by Herschel: “Notice of a remarkable Photographic Process by which Dormant Pictures are produced capable of Development by the Breath, or by keeping in a Moist Atmosphere.” In the Philosophical Transactions for 1843 we find another memoir contributed to the Royal Society: “On Certain Improvements in Photographic Processes described in a former communication, and on the Parathermic Rays of the Solar Spectrum.” This communication was made on 24th November, and is, in effect, a continuation of the two former memoirs, the numbering of the paragraphs running continuously throughout. At the York meeting of the British Association, held in September, 1844, Herschel announced a new photo graphic process, to which he gave the name of amphitype, a term suggested by Talbot, in consequence of the picture, according to the method adopted in the subsequent mani pulations, becoming either a positive or a negative repro duction. It may be here remarked that Herschel, in all these experiments, seems to have used engravings instead of the ordinary negative. Herschel, from his researches, had realised the fact that silver bromide was more sensitive to light, or, rather, that it was affected by a wider range of the rays forming the solar spectrum, than silver iodide, which formed the staple of Calotype, and afterwards that of the collodion process. Accordingly, when the Photo graphic Society of London was formed, in 1853, among the first contributions to its transactions we find one from Herschel, “ On the Substitution of Bromine for Iodine in Photographic Processes.” This paper was read 2nd June, and I may be allowed to quote one pregnant sentence from it, which may almost be regarded as prophetic—“ A new photography has to be created, of which bromine is the basis.” In 1855 Herschel advocated the desirability of securing daily photographic representations of the sun. The original communication was read before the Astro nomical Society, and will be found in the volume for 1854-55 of the monthly notices of the Society. It is also to be found reported in the Athenieum, in No. 1,435. In 1858, at the Leeds meeting of the British Association, Herschel presided over section B, the chemical, and his introductory remarks, so far as they relate to our own science of photography, may be appropriately quoted. The words used by Herschel in 1858 are no less significant in our own day:— “Hitherto the more attractive applications of photo graphy have had too much the effect of distracting the attention from the purely chemical question which it raises, but the more we consider them in the abstract, the more strongly they force themselves on our notice, and I look forward to their occupying a much larger space in the domain of chemical enquiry than is the case at pi esent.” The same sentiment regarding photography has been otherwise expressed by Major Russell, who is credited with having said that photography would be a most inter esting subject were it not for the pictures. In 1859 an article from Herschel appeared in the second volume of the Photographic News, in the number for July 22nd, “The Action of the Solar Spectrum upon Certain Compounds of Silver,” and in the third volume of the same paper, in the number for September 9th, under the same title, a further communication is to be found. This article has an accompanying illustration of the apparatus employed by the author in securing his spectra impressions. In the Photographic News of May 11th, 1860 (Vol. IV.), Herschel contributes an article, “Instantaneous Photo graphy.” He discusses the possibility of taking a rapid series of pictures of moving objects, and recombining them in the optical apparatus, the phenakistiscope. The appearance of motion is again imparted to the eye when the pictures are rapidly revolved. This method, as you are all aware, has been adopted by Muybridge. A term is used by Herschel in this communication which, although common enough now-a-days, is very significant, and describes well the taking of an instantaneous picture. I refer to the term snap-shot. I make the statement subject, of course, to correction, but I think we may give to Herschel the credit of coining this photographic term for us equally with the better known terms of positive and negative. In 1861, in the eighth volume, p. 384, of the Britinh Journal of Photograpluj, Herschel contributes an article, “ Forms of Lenses suited for Destroying Spherical Aberra tion.” The foregoing represents an epitome of the work done by Herschel. We will now consider Talbot’s share in the development of our art. Talbot’s experimental photographic work appears to have been begun about the year 1834. By means of paper impregnated with silver chloride, Talbot asserts that he had secured camera pictures of his residence as early as 1835 (yide appendix to second addition of “ Tissandier's Photography,” written by Talbot). It was not, however, till January 25th, 1839, at one of the Friday meetings of the Royal Institution, that the process was first publicly announced, and as Faraday, who brought the matter forward, explained, it was done so for the purpose of “ establishing a date." Daguerre’s process had been announced in January, but the particulars were only known to his friend Arago. Talbot had in the meantime sent in a paper to the Royal Society, and he was afraid that Daguerre’s process might be divulged before his com munication to the Royal Society was published. On the Thursday following, however—viz., the 31st January, 1839 —Talbot’s paper, entitled “ Some Account of the Art of Photographic Drawing ; or, the Process by which Natural Objects may be made to Delineate themselves without the aid of the Artist’s Pencil," was read. The paper was not published in the “Philosophical Transactions,” but an abstract of it is given in the “Proceedings of the Royal Society,” vol. iv., p. 120. It was printed in extenso in the London and Edinburgh Philosophical Magazine, March, 1839, vol. xiv., p. 209. Both at the Royal Institution meeting, and that of the Royal Society, specimens of “ photogenic drawing ” were exhibited, along with the camera pictures of Talbot’s residence. On the 21st Feb., 1839, a paper, entitled “ An Account of the Processes Employed in Photogenic Drawing,” was communicated to the Royal Society. The memoir divides itself into two parts, first the preparation of the paper, and secondly the fixing of the design, which was effected by a solution of potassium iodide of the proper strength, or by a strong solution of sodium chloride. Talbot at this stage was doing little more than producing negative designs from opaque natural objects. (To be continued.)