‎"BUNSEN, ROBERT & HENRY E. ROSCOE. - THE LAWS OF PHOTOCHEMICAL ACTION.‎
‎Photo-chemical Researches. - Part IV. Received May 26 - Read May 26, 1859.‎

‎(London, Taylor and Francis, 1860). 4to. No wrappers as extracted from ""Philosophical Transactions"" 1859 - Vol. 149 - Part II. Pp. 879-926. Clean and fine.‎

Reference : 42633

‎First appearance in English of a classic paper in the investigations of chemical reactions produced by lightrays. Their joined work - from 1855-59 - founded scientific photochemistry, by determining the phenomena of induction, deduction and extinction. They found that the beginning of light reaction takes place at first very slowly and that the velocity increases gradually until it attains a constant value, observing also that steam accelerates the action and that air retards it. They also gave proofs of the ""Law of Reciprocity‎