expansion valve (ekspanshonvalv)

In a steam-engine, a valve which shuts off the steam in its pa age to the slide-valves when the piston has traveled a certain distance in the cylinder, leaving the remaining part of the stroke to be performed by the expansion of the steam. See expansion - gear. expansive (eks-pan's iv), a. [= F. expansif = Sp. Pg. expansivo, This internal pre ure, resulting from the solidifying of the fluid particles in the interstices of the ice, acts on the ma of the ice as an expansive force. J. Croll, Climate and Cosmology, p. 253. 2. Capable of being expanded, or of expanding or spreading out in volume or extent; dilatable: as, the expansive quality of air; expansive gases or substances. Then no more Th' expansive atmosphere is cramp'd with cold; But, full of life and vivifying soul, Lifts the light clouds sublime. Thomson, Spring. 3. Embracing a large number of objects or particulars; wide-extending; comprehensive: as, expansive benevolence; an expansive outlook. A distant view of Ægin a and of Megara, of the Pireus and of Corinth, melted the soul of an ancient Roman, for a while suspended his private sorrows, and absorbed his sense of personal affliction in a more exp an sive and generous compa ion for the fate of cities and states. Eustace, Tour through Italy, x. space: see space.] I. in trans. 1. To move at large; rove without prescribed limits; wander without restraint. I never travelled but in map or card, in which my unconfined thoughts have freely expatiated . Burton, Anat. of Mel., To the Reader, p. 16. Pope , Windsor Forest, 1. 254. Religion contracts the circle of our pleasures, but leaves it wide enough for her votaries to expatiate therein. Add is on, Spectator, No. 494. Like winter flies, which in mild weather crawl out from obscure nooks and crannies to expatiate in the sun. Bids his free soul expatiate in the skies. Lowell , Biglow Papers, 2d ser., p. 79. 2. To enlarge in discourse or writing; be copious in argument or discu ion: with on or upon. [He] talked with ease, and could expatiate upon the common topics of conversation with fluency. Goldsmith, Vicar, vii. The pa ions of kings are often expatiated on ; but, in the present anti-monarchical period [time of Charles I.], the pa ions of parliaments are not imaginable! 1. D'Israeli , Curios. of Lit., IV. 380. II. trans. To allow to range at large; give free exercise to; expand; broaden. [Rare.] How can a society of merchants have large minds, and extheir thoughts and publick undertakings, whose constitution is subject to such frequent changes, and who every year run the risk of their capital? C. Davenant, E ays on Trade, II. 421. expatiation (eks-pā-shi-a's hon), n. [ expatiate + -ion .] The act of expatiating. Take them from the devil's latitudes and expatiations ; from the infinite mazes and bypaths of error. Farindon , Sermons (1647), I. ii.