AXIOM (an assumption), a universal proposition, which the understanding must per ceive to be true as soon as it perceives the meaning of the words, though it cannot be proved. It is, therefore, called a self-evident truth. In mathematics, axioms are those propo sitions which are assumed without proof, as be ing in themselves independent of proof, and which are made the basis of all the subsequent reasoning. Euclid has assumed 15 axioms as the basis of geometry. Among these are: 'The whole is greater than its parts; ((Things that are equal to the same thing are equal to one another' ; ((Magnitudes which coincide, that is, which exactly fill the same space, are equal to one another in every respect.* Bacon calls axiom a general principle, obtained by experi ment and observation, from which we may safely proceed to reason in all other instances; and Newton gives the name of axiom to the laws of motion, which, of course, are ascer tained by the investigation of nature; he also terms axioms those general experimental truths or facts which form the groundwork of the science of optics.
AXIS (in crystallography). See CRYSTAL.
AXIS (Latin, of unknown origin), a white-spotted deer (Axis axis) of India and the East Indies, known locally among the Hin dus as Dchitra,* among the English as the °hog
It resembles the European fallow deer in size and color, and as it is easily domesti cated, is a favorite in European parks. The slender, sharp-pointed horns are not palmated and only a little branched, while the female is hornless. It is timid and usually goes in small herds, in which females largely predominate. It lives in thick jungles near water, and usually feeds in the night. Colored plates, illustrating its varieties, are given in Lydekker's