An experimental enquiry into the nature of the radiant heating effects from terrestrial sources

Abstract

In this paper the author first states the opinion of various prece­ding experimenters on the subject of the heat evolved from non-luminous sources, and from bodies in various degrees of luminosity, and observes that all the facts may be accounted for, by supposing two distinct heating influences, one associated in some very close way with the rays of light, and carried as it were by them through a glass screen without heating it, the other being merely simple radiant heat affected by the screen, exactly as the radiant heat from a non-luminous body. In order to examine the truth of this explanation, he observes fur­ther, that it is not sufficient to observe the effects produced by the intervention of the screen alone, we must combine this with an in­quiry into the relations to surfaces of the portions of the heat stopped and transmitted; that is to say, we must endeavour to discover whe­ther the portions differ in any other respect than merely in transmissibility.