Pictet's Proposal to Dissociate the Metalloid Elements

Abstract

THE task set before me is to expound in as simple and intelligible language as possible the remarkable train of reasoning which has led M. Raoul Pictet, of Geneva, to the conclusion that the so-called metalloids are really not elementary bodies at all, but capable of dissociation into simpler forms. During the last two years M. Pictet has published several important memoirs upon different branches of thermo-dynamics, and has, as is well-known, in his researches on the liquefaction of oxygen and of hydrogen shown the fruitfulness of the ideas which have thus occupied him. He is at the present moment engaged upon a large volume entitled Synthèse de la Chaleur, a work in which it is sought to deduce all the known laws of heat from the general principles of theoretical mechanics, by finding true mathematical definitions.for the quantities which hitherto have been usually expressed as simple experimental matters. Thus the terms “temperature,” “specific heat,” “latent heat,” &c., are capable of exact definition in a manner which enables the relations bet ween them to be investigated, analytically. These relations thus investigated are found by M. Pictet to be capable of experimental verification, and the complete acccordance of deduced theory with observed fact justifies him in giving the name of Synthesis of Heat to this new advance in thermo-dynamics.