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precipitation|prɪsɪpɪˈteɪʃən|
[a. F. précipitation (15th c. Godef. Compl.), ad. L. præcipitātiōnem, n. of action from præcipitāre to precipitate.]
The action of precipitating.
I.
1. a. The action of casting down or falling headlong from a height; a hurling down; the fact of being hurled down; headlong fall or descent.
1607Shakes. Cor. iii. iii. 102 Wee..banish him our Citie In perill of precipitation From off the Rocke Tarpeian. 1720Welton Suffer. Son of God II. xvi. 427 Under this Assurance that He might cast Himself down from the Pinnacle, but that He should be supported in His Precipitation as well as He was in His Ascent thither. 1856Stanley Sinai & Pal. x. (1858) 367 The summit of a mountain, from which summit the intended precipitation was to take place.
b. Steepness of descent; precipitousness. rare.
1607Shakes. Cor. iii. ii. 4 Let them..pile ten hilles on the Tarpeian Rocke, That the precipitation might downe stretch Below the beame of sight. 1890Talmage Manger to Throne 53 The hills for width and precipitation are displays omnipotent.
c. Path. Complete prolapsus, ‘falling’.
1612tr. Guillemeau's Child-birth 210 The precipitation, or comming downe of the wombe: the ligaments being loosened, and sometimes broken. 1822–34Good's Study Med. (ed. 4) IV. 110 note, In what Madame Boivin terms precipitation or complete prolapsus..any rational scheme of relief is entitled to encouragement.
†d. Vertical descent (of a root). Obs. rare.
1669J. Rose Eng. Vineyard (1675) 18 The deepness, and fatness of the earth, contributes more to the luxury of the branches..and precipitation of the roots, than to the just, and natural stature of the stem.
II.
2. Headlong rush, violent onward motion.
1628Feltham Resolves ii. [i] x. 26 Wee goe surest, when we post not in a precipitation. 1695Woodward Nat. Hist. Earth (J.), The hurry, precipitation, and rapid motion of the water, returning at the end of the deluge, towards the sea. 1748Anson's Voy. i. viii. 76 The violence of the current, which had set us with so much precipitation to the eastward. 1822Lamb Elia Ser. i. Chimney-Sweepers, Pacing along Cheapside with my accustomed precipitation when I walk westward.
3. a. Sudden and hurried action; sudden haste or quickness; hurry.
1502Ord. Crysten Men (W. de W.) iv. vi. S ij, He therin ought to procede demeurely dyscretly, without preceptacyon [Fr. precipitacion] in chastysynge. 1589Puttenham Eng. Poesie ii. xi. (Arb.) 98 Mounting and falling from note to note such as be to them peculiar, and with more or lesse leasure or precip[it]ation. 1678Trans. Crt. Spain 165 That so he might undo me with greater precipitation. 1782F. Burney Cecilia viii. vi, ‘None, none!’ interrupted she, with precipitation. 1838Dickens Nich. Nick. vii, The lady having seized it, with great precipitation, they retired.
b. Unduly hurried action; inconsiderate haste; rash rapidity.
1629T. Adams Medit. Creed Wks. 1862 III. 119 Precipitation in our works makes us unlike to God: heady fool, art thou wiser than thy Maker? 1700J. A. Astry tr. Saavedra-Faxardo I. 251 Precipitation is the effect of Madness, and generally the occasion of great Perils. 1794S. Williams Vermont 397 Some philosophers, with great precipitation have pretended to decide it by system. 1870Disraeli Lothair xi, We must not act with precipitation.
4. The bringing on of something hastily, suddenly, or before the expected time; hastening, hurrying; acceleration.
1621in Elsing Debates Ho. Lords (Camden) 109 Then the precipitacion of justice (not hearing the proofes) is hyghe injustice. 1646Sir T. Browne Pseud. Ep. 174 The common cause alleadged..is, a precipitation or over hasty exclusion before the birth be perfect. 1769Goldsm. Hist. Rome (1786) II. 488 This, in a great measure, gave precipitation to his own downfall. 1882Farrar Early Chr. I. 557 note, He attributes to his death the precipitation of the ruin of Jerusalem.
III. 5. a. Chem. Separation and deposition of a substance in a solid (powdery or crystalline) form from solution in a liquid, by the action of a chemical reagent, or of electricity, heat, etc.; the removal and deposition of particulate matter from suspension in a gas; the separation of crystals of a solute phase from a solid solution (see also precipitation hardening below).
The date of first quotation is not certain: it may be 17th c.
[1477Norton Ord. Alch. vi. in Ashm. Theat. Chem. Brit. (1652) 95 Longe Vessells for Precipitation.] 1612Woodall Surg. Mate Wks. (1653) 273 Precipitation is when bodies corroded by Aqua fortis, or Aqua Regia, and dissolved into water..are reverberated into Calx. 1660Boyle New Exp. Phys. Mech. xxxvii. 313 The precipitation of Benjamin, and some other Resinous Bodies. 1790Keir in Phil. Trans. LXXX. 374 Upon adding iron to a solution of silver in the nitrous acid no precipitation ensued. 1800Henry Epit. Chem. (1808) 12 For precipitations, and separating liquids from precipitates, the decanting-jar will be found useful. 1900Jrnl. Soc. Dyers XVI. 6 The precipitation of the indigo white. 1908F. G. Cottrell U.S. Patent 895,729 2/1 The gases or vapors containing the suspended particles enter the precipitation chamber A through pipe B. 1912,1920[see electrostatic a.]. 1926Trans. Amer. Soc. Steel Treating X. 718 The idea that the hardness of an alloy may be increased by the precipitation of a soluble constituent from solid solution was first advanced by Merica and his associates in a hypothesis to account for the age-hardening of duralumin. 1938Trans. Inst. Chem. Engineers XVI. 37/2 It is unlikely that any new cement works will be designed without provision for dust separation by electrical precipitation. 1958A. D. Merriman Dict. Metallurgy 3/1 Ageing, a precipitation process, often submicroscopic, which occurs when a supersaturated solid solution is allowed to rest at atmospheric temperature after quenching. 1967A. H. Cottrell Introd. Metallurgy xx. 372 Cu-Be alloys soften rapidly by discontinuous precipitation at temperatures above about 300°C, but this can be prevented by the addition of about 0·4 wt per cent cobalt. 1974Encycl. Brit. Macropædia IV. 161/1 Electrostatic precipitation is a method for the precipitation of fogs..: a high voltage is applied across the gas phase to produce electrical charges on the particles. These charges cause the particles to be attracted to the oppositely charged walls of the separator.
b. concr. The product of this process, a precipitated substance; a precipitate. (In quot. 1867 in extended sense.)
1605Timme Quersit. iii. 154 The same coagulating force..doth manifestly appeare in those preparations which are called precipitations. 1867H. Macmillan Bible Teach. Pref. (1870) 12 Our forests, corn-fields, and coal-beds are the solid precipitations of unseen carbonic acid gas in the atmosphere.
c. attrib.
1839Ure Dict. Arts 37 The clear liquor should now be run off into the precipitation cistern. 1887Pall Mall G. 11 Jan. 2/2 The construction of precipitation works at one of the London sewage outfalls.
6. a. Physics and Meteorol. Condensation and deposition of moisture from the state of vapour, as by cooling; esp. in the formation of dew, rain, snow, etc. b. concr. That which is so deposited.
1675Phil. Trans. X. 468 In some..precipitations of the Air. 1692Ray Disc. ii. ii. (1732) 99 There was so strange a Condensation or rather Precipitation of the Vapours. 1812–16Playfair Nat. Phil. (1819) I. 322 Dew is a precipitation of humidity from the lower strata of the atmosphere. 1859R. F. Burton Centr. Afr. in Jrnl. Geog. Soc. XXIX. 105 Thence the frequent precipitation of heavy rain, and the banks and sheets of morning cloud which veil the tree-clad peaks of the highest gradients. 1864Marsh Man & Nat. 436 Marriotte found that but one sixth of the precipitation in basin of the Seine was delivered into the sea by that river. 1878Huxley Physiogr. 179 The excess of evaporation over precipitation in the northern portion of the land hemisphere.
7. fig.; spec. in Spiritualism = materialization 2.
1891Pall Mall G. 1 Oct. 2/3 A distinguished naturalist..assured me that he had, in his own room, with no other person present save his servant, a young man of ‘mediumistic’ temperament, repeatedly witnessed the process of materialization (precipitation) of a human figure slowly going on under his own eyes, developing from a nebulous shape through which he could see the furniture beyond it, to a solid human form, whose hand he could grasp firmly.
8. Special Comb.: precipitation hardening Metallurgy, hardening of an alloy by heat treatment that causes the precipitation from solid solution of crystals of a solute phase; a strengthening process utilizing this phenomenon.
1926R. S. Archer in Trans. Amer. Soc. Steel Treating X. 719 It is proposed in this paper..to develop the general theory of what may be called ‘precipitation hardening’. 1931Jrnl. Iron & Steel Inst. CXXIV. 671 The binary iron-boron alloys were incapable of hardening by quenching and the precipitation hardening was hardly noticeable. 1957Technology Oct. 291/2 Parts made from it [sc. a new stainless steel] are subjected to ‘precipitation hardening’, a method of heat treatment designed to give increased strength by precipitating an inter-metallic compound between the metal particles. 1973J. G. Tweeddale Materials Technol. I. vi. 169 Precipitation hardening..is a three-part treatment (1) a solution treatment at elevated temperature to dissolve the solute (2) a quenching operation to trap the solute..(3) a precipitation or ageing treatment to develop the required size of precipitate. |