[57] The meaning of this metaphor has probably been affected by the other meaning of _spring_ (as in _well-spring_), but this did not occur till later. [58] Not only is the word _pump_ constantly used to describe the heart’s action, but one must also consider its reaction on the meaning of older physiological terms such as _valve_. _Pump_, with the meaning ‘ship’s pump’, is found in English in the fifteenth century, but in the sense of ‘instrument for raising water’ it is unknown to the Teutonic languages before the sixteenth century, though instruments of some sort had been used for that purpose in classical times. An understanding of the underlying mechanical principle, however, only developed, as we should expect, in the seventeenth century, when the words _suction_ and _hydraulic_ appeared in, for instance, Bacon’s writings. Harvey published his treatise, _De motu cordis e sanguinis_, in 1628. [59] Especially in conjunction with such epithets as _primeval_ or _primal_, in which combination these words have frequently been made to bear a considerable part of the suggestiveness and meaning long ago worked into such words as _creation_, _mystery_, _sacrament_, _the Word_, ... (see previous chapters). [60] See p. 149. [61] Of English words beginning with ‘iso-‘—a Greek prefix meaning ‘of equal measurement’ (_isosceles_, ‘equal legged’, _isobar_, ‘equal pressure’, ...), about twelve came in before the nineteenth century, about seventy in the course of it. [62] Wyclif had used it in a good sense. [63] “There is no God—but this is a family secret.” [64] Huxley, in whose imagination was to some extent epitomized what was proceeding in varying degrees of intensity in minds all over Europe, describes Nature as a “materialized logical process”. [65] _Spiritualist_, however, is found as early as the middle of the seventeenth century; but it was employed in the sense of ‘fanatical’, etc., or with the more technical meaning of ‘one who supports ecclesiastical authority’. Its use as a purely philosophical designation seems to date from about the middle of the nineteenth century, and the modern “table-rapping” implication is later still. There is now a tendency to substitute _spiritism_, _spiritist_, ... in the latter sense. [66] Both these words referred at the time of their introduction to the new doctrine that Christ was a purely human figure. [67] 1820; but _introspection_ was given its modern meaning by Dryden. [68] Hence the titles of our University Degrees—_Bachelor of Arts_, _Master of Arts_,... [69] Poets were regularly called _makers_ in the fourteenth and fifteenth centuries. “I know not”, says Sidney, “whether by luck or wisdom we Englishmen have met with the Greeks in calling him a ‘maker’.” [70] See pp. 79-80. [71] See p. 32. [72] London emporiums even advertise themselves in chatty essays entitled _The Creative Aspect of a Store_.