Hinc elementum ignis cum orbe suo introductum est. Bacon saw in fire the mere result of a certain combination of action, and was consequently led to deny its elementary character. The ancient physicists attributed an orbit to each of the four elements, into which they resolved the universe, and supposed their spheres to involve each other. The orbit of the earth was in the centre, that of fire at the circumference. For Bacon’s inquisition into the nature of heat, and its complete failure, see the commencement of the second book of the Novum Organum.—Ed.