actinism
(ˈæktɪnɪz(ə)m)
[f. Gr. ἀκτῖν- ray + -ism.]
† 1. ‘The radiation of heat or light, or that branch of Philosophy which treats of it.’ Craig 1847. Obs.
2. That property or force in the sun's rays by which chemical changes are produced, as in photography.
| 1844 R. Hunt Brit. Assoc. Report 30 By a most careful prismatic analysis of the rays..I have ascertained the relative quantity of the active chemical principle (Actinism). 1849 Lindley Elem. Bot. 56 Mr. Hunt believes that the germination of seeds in the spring..is dependent upon the variations in the amount of actinism—or chemical influence—of light and of heat in the solar beam. 1862 R. H. Patterson Ess. Hist. & Art 13 The electro-positive and electro-negative rays, of which Heat and Actinism are the representatives. |