History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c39.s5.3

c39.s5.3

A substance is an aggregate of the former kind, and may be divided into two classes; (1) the *bhutas* and their isomeric modifications, and (2) chemical compounds. Chemical compounds again may be subdivided into two classes, (1) those composed of atoms of the same *bhuta* class, *i.e.*, of different isomeric modifications of the same *bhuta*, and (2) those composed of atoms of different *bhuta* classes. In the first case, there is contact between isomeric atoms, in the second case, between heterogeneous or polymeric atoms The first contact leads to intimate union: the isomeric atoms by a peculiar liberation of Energy are attracted towards one another, and being riveted as it were, form the so-called material cause of the compound product. The second kind of contact (between unlike atoms of heterogeneous *bhutas*) begins with a liberation of Energy, which breaks up each of the *bhutas*, and, taking particles (or atoms) of one as nuclei or radicles, groups particles of the rest around these radicles in a comparatively free or unattached condition. In this case, one *bhuta*, that which serves to furnish the radicles, not necessarily that which is numerically or quantitatively predominant, gets the name of "material cause", and the others, which by their collocation cause the liberation of Energy, are called "efficient causes."