A Manual Of Photography

CHAPTER IV. ilAGUERREOTYPE THE DISCOVERY OF M. DAGUERRE. Section I.__ The Original Process of Daguerre. has, been already stated that Niepce and Daguerre having i i they were prosecuting experiments of klnd' entered into a partnership. On the 5th Dec Niepce communicated to Daguerre the particulars of the process employed by him, which has been already described (Vaap. 11), under the term Heliograpiiy. Niepce died in uy h333, but he has left some letters which clearly show that ne had been a most industrious investigator. One extract appears of particular importance : — “ I repeat it, sir,” he says 1do not see that we can hope to derive any advantage from us process (Me use of iodine) more than from any other method which depends upon the use of metallic osides, Ac® he says, “ a decoction of Thlaspi (Shepherd’s purse), • Phosphorus, and particularly of sulphur, as acting on 1? 5E way as iodine,, and caloric, produce the same by oxidising the metal, for from this cause proceeded in “stances their extreme sensibility to light.” After the •IO icépliore Niepce, a new agreement was entered r ootween lus son,M. Isidore Niepce and Daguerre, that ey should pursue their investigations in common, and share the f ronts whatever they might eventually prove to be. he discovery of Daguerre was reported to the world early in anuary, 1839 ; but the process by which his beautiful pictures ere produced was not made known until the July following ? Was Passed securing to himself a pension for life 0,000 francs, and to M. Isidore Niepce, the son of M. Nience °ve mentioned, a pension for life of 4,000 francs, with one half thronte their widows. It is to be regretted, that after of rench Government had thus liberally purchased the secret °f the Daguerreotype, for “ the glory of ^^nce and of art with one of the most surprising