#169.  Unproductiveness.—­ N. unproductiveness &c. adj.; infertility,
sterility, infecundity[obs3]; masturbation; impotence &c. 158; unprofitableness &c. (inutility) 645.
     waste, desert, Sahara, wild, wilderness, howling wilderness. 
     V. be — unproductive &c. adj.; hang fire, flash in the pan, come to
nothing.
     [make unproductive] sterilize, addle; disable, inactivate. 
     Adj. unproductive, acarpous[obs3], inoperative, barren, addled,
infertile, unfertile, unprolific[obs3], arid, sterile, unfruitful, infecund[obs3]; sine prole; fallow; teemless[obs3], issueless[obs3], fruitless; unprofitable &c. (useless) 645; null and void, of no effect.

     #170.  Agency.—­ N. agency, operation, force, working, strain,
function, office, maintenance, exercise, work, swing, play; interworking[obs3], interaction; procurement.
     causation &c. 153; instrumentality &c. 631; influence &c. 175; action
&c. (voluntary) 680; modus operandi &c. 627.
     quickening power, maintaining power, sustaining power; home stroke. 
     V. be -in action &c. adj.; operate, work; act, act upon; perform,
play, support, sustain, strain, maintain, take effect, quicken, strike.
     come play, come bring into operation; have play, have free play; bring
to bear upon. 
     Adj. operative, efficient, efficacious, practical, effectual.
     at work, on foot; acting &c. (doing) 680; in operation, in force, in
action, in play, in exercise; acted upon, wrought upon. 
     Adv. by the -agency &c. n.- of; through &c. (instrumentality) 631; by
means of &c. 632. 
     Phr.  “I myself must mix with action lest I wither by despair”
[Tennyson].

—­ p. 51 —­

     #171.  Physical Energy.—­ N. energy, physical energy, force, power &c.
157; keenness &c. adj.; intensity, vigor, strength, elasticity; go; high pressure; fire; rush.
     acrimony, acritude[obs3]; causiticity[obs3], virulence; poignancy;
harshness &c. adj.; severity, edge, point; pungency &c. 392.
     cantharides; seasoning &c. (condiment) 393.
     activity, agitation, effervescence; ferment, fermentation; ebullition,
splutter, perturbation, stir, bustle; voluntary energy &c. 682; quicksilver.
     resolution &c. (mental energy) 604; exertion &c. (effort) 686;
excitation &c. (mental) 824. 
     V. give -energy &c. n.; energize, stimulate, kindle, excite, exert;
sharpen, intensify; inflame &c. (render violent) 173; wind up &c. (strengthen) 159.
     strike home, into home, hard home; make an impression. 
     Adj. strong, energetic, forcible, active; intense, deep-dyed, severe,
keen, vivid, sharp, acute, incisive, trenchant, brisk.
     rousing, irritation; poignant; virulent, caustic, corrosive, mordant,
harsh, stringent; double-edged, double-shotted[obs3], double-distilled; drastic, escharotic|; racy &c. (pungent) 392.
     potent &c. (powerful) 157; radioactive. 
     Adv. strongly &c. adj.; fortiter in re[Lat]; with telling effect. 
     Phr. the steam is up; vires acquirit eundo[Lat]; “the race by vigor
not by vaunts is won” [Pope].