FIRMAMENT (La t. firmament um , from firmarr, to strengthen. from firui is, firm). A word used to denote the vault of heaven. The term found its way into English from the Vul gate. which renders the Septuagint arepIuma, sterelima, and the Hebrew reqi'a by the Latin firmamentum (Clem i. (1). Raqi`a (from t verb raga', to extend) signifies whatever is beat • en or stretched out, and was especially employed by the Hebrews to denote the hemisphere above the earth, eompared (Ex. xxiv. TO) to a splendid and pellucid sapphire. Elsewhere (Ez. i. 22-26) it is spoken of as the 'floor' on which the throne of the Most High is placed. Hence it follows that the notions of solidity and expansion were both contained in the Hebrew conception of the firmament (Job x.xxvii. 18). The blue ethereal sky was regarded as a solid sphere, to which the stars were fixed, and which was constantly re volving, carrying them with it. This sphere or firmament rested on the loftiest mountains as pillars and divided the waters which were under the firmament from the waters which were above the firmament; and the theory of the phenomena of rain, etc., was that there were 'windows in
heaven'—i.e. in the firmament—through which, when opened, the waters that were above the firmament descended (Gen. vii. 11; II. Kings vii. 2, 19; Ps. lxxviii. 23 and cxlviii. 4). Simi larly, under the earth there was another sea, called the 'deep' or 'great deep.' The view enter tained by the Creeks and other early nations was essentially the same. It is most probable, at least in the ease of the Jews and the Baby lonians, that both views are traceable to the same original source. In the progress of astro nomical observations it was found that many of the heavenly bodies had independent motions inconsistent with the notion of their being fixed to one sphere or firmament. Then the number of crystalline spheres was indefinitely increased, each body that was clearly independent of the rest having one assigned to it, till a complex system was introduced capable of being fully understood only by the philosophers who devised it. See PTOLEMAIC SYSTEM.