Also 5 valwe, 7 value. [ad. L. valva leaf of a door (usu. pl. valvæ a folding door). So F. valve (1611), Pg. valva.]
I. 1. One or other of the halves or leaves of a double or folding door.
1387. Trevisa, Higden (Rolls), IV. 449. At þe laste þey brende þe valves of þe temple þet were i-heled wit gold.
c. 1440. Promp. Parv., 508/1. Valwe, valva, vel valve.
1661. Blount, Glossogr. (ed. 2), Valves, folding doors or windows.
1718. Pope, Odyss., I. 555. The bolt, obedient to the silken cord, To the strong staple’s inmost depth restored, Secured the valves.
1834. Beckford, Italy, I. 326. Throwing open the valves, we entered the chapel.
1863. Baring-Gould, Iceland, 280. The outside of the valves [of the triptych] was painted with figures of S. John the Baptist and Moses.
1871. B. Taylor, Faust (1875), II. III. 164. Ye valves of yon dark iron portals!
transf. c. 1530. Judic. Urines, I. iii. 8. For to delyuer and purge them oute by that membre, that is to say, by the matryce, and so out by the value, that is to say, by ye gate of hyr body.
b. A door controlling the flow of water in a sluice.
1790. Act 33 Geo. III., c. 90 § 65. If any Person … cause to be opened … any Lock Gate, or any Paddle, Valve, or Clough, belonging to any Lock … on the said Canal.
1847. Dwyer, Princ. & Pract. Hydraul. Engin., 74. The gate or valve of a sluice is generally made to move by machinery in a vertical position.
2. a. Conch. One of the halves of a hinged shell; a single shell of similar form; a single part of a compound shell.
1661. Lovell, Hist. Anim. & Min., Isagoge b 7 b. Some are covered on every side, as oisters, cocks, and tellinæ; others have but one valve, the other side sticking to rocks.
1771. Phil. Trans., LXI. 232. I separated the valves, and the rising part of the hinge to the edge shewed them to be shells.
1774. Goldsm., Nat. Hist. (1776), VII. 69. These shells take different forms, and are often composed of a different number of valves; sometimes six; sometimes but three.
1828. Stark, Elem. Nat. Hist., II. 80. The hollow valve of this species … was formerly used as a drinking cup. Ibid. The lower valve white, and longitudinally sulcated; upper valve rufous.
1871. T. R. Jones, Anim. Kingd. (ed. 4), 540. The elastic ligament for opening the valves … being placed externally instead of within the shell.
b. Ent. (See quot.)
1826. Kirby & Sp., Entomol., xxxiii. III. 390. Valvæ (the Valves), two lateral laminae, often coriaceous, by which the ovipositor when unemployed is covered.
3. Bot. a. One of the halves or sections of a dehiscent pod, pericarp, or capsule.
1760. J. Lee, Introd. Bot., I. vi. (1765), 13. Siliqua, a Pod, is a Pericarpium of two Valves, wherein the Seeds are fastened along both the Sutures or Joinings of the Valves.
1796. Withering, Brit. Plants (ed. 3), I. 294. Pod long, cylindrical;… valves 2, opening with a jerk, and the valves rolling back.
1861. Bentley, Man. Bot., 452. The valves of the fruit opening longitudinally, and bearing transverse septa in their interior.
1870. Hooker, Stud. Flora, 235. Capsule globose;… valves septiferous.
b. In various applications (see quots.).
1785. Martyn, Lett. Bot., xiii. (1794), 130. The inner [chaff] consisting also of two parts or valves, which you may call petals.
1796. Withering, Brit. Plants (ed. 3), I. 176. Bloss[om]. 1 petal, funnel-shaped. Tube cylindrical, crooked…. Mouth closed by 5 prominent, convex, approaching valves.
1812. New Bot. Gard., I. 23. The stamina have six filaments, subulate, inserted into the valves of the nectary.
1832. Lindley, Introd. Bot., 104. The pieces of which these three classes of bracteæ are composed are called valves or valvulæ by the greater part of botanists. Ibid., 126. In the most common state of the anther the cells … open with two valves, by a longitudinal fissure from the base to the apex.
1857. Henfrey, Bot., § 629. The cells [of Diatomaceæ] … enclosed by a membrane … impregnated with silex and separable into valves.
1870. Hooker, Stud. Flora, 12. Anthers opening by 2 ascending lids or valves.
II. 4. Anat. A membranous fold in an organ or passage of the body (esp. in the heart, arteries, and veins) that automatically closes after the manner of a trap-door to prevent the reflux of blood or other fluid.
1615. Crooke, Body of Man, 180. In each of these passages there are Values which hinder the refluence of the choler.
1653. More, Antid. Ath., Scholia II. xii. § 6. As to the Fabrick of the Valves and Veins of the Heart.
1688. Boyle, Final Causes, iv. 157. Our famous Harvey … took notice that the valves in the veins … were so placed that they gave free passage to the blood towards the heart.
1799. Med. Jrnl., II. 371. This foramen in the embryo … is closed by a valve which prevents the reflux of the blood.
1830. R. Knox, Béclard’s Anat., 208. The valves … close the vein, sustain the blood, and prevent its reflux towards the capillary vessels.
1870. Rolleston, Anim. Life, p. xlv. The valves, which in other Vertebrata guard the entrance of the great veins into the right auricle.
b. A similar part or structure serving to close a passage for other reasons.
1805. Bingley, Anim. Biog. (ed. 3), I. 97. Within each [ear] there is a kind of secondary auricle … so placed as to serve for a valve or guard to the auditory passage. Ibid. (1813), (ed. 4), I. 110. The ears are short, and have each a very small inner valve.
1835–6. Todd’s Cycl. Anat., I. 322/1. The pyloric orifice of the gizzard is guarded by a valve in many birds.
1863. A. M. Bell, Princ. Speech, 192. When the Stammerer has brought the valve of the throat—the glottis—under due control.
fig. 1871. R. H. Hutton, Ess. (1877), I. 74. Animals … have, so to say, fewer valves in their moral constitution for the entrance of divine guidance.
† 5. A supposed check (similar to above) to the reflux of sap in plants. Obs.
1664. Phil. Trans., I. 30. About the Pores of bodies, and a kind of Valves in wood.
1673–4. Grew, Anat. Pl., Anat. Trunks (1682), 126. Which … plainly shews, That in the Sap-Vessels of a Plant, there are no Valves.
a. 1704. Locke, Elem. Nat. Phil., ix. (1754), 35. The heat dilating, and the cold contracting those little tubes; supposing there be valves in them, it is easy to be conceived how the circulation is performed in plants.
1807. Vancouver, Agric. Devon (1813), 435. These valves possess a contractile force,… whereby the regress of the moisture is prevented, and of course it is taken up by the tree.
6. Mech. A device of the nature of a flap, lid, plug, etc., applied to a pipe or aperture to control the passage of air, steam, water or the like, usually acting automatically by yielding to pressure in one direction only.
Many classes and varieties of valves are in use, and are distinguished by special epithets denoting form or purpose, as ball-, clack-, cone-, disk-, flap-valve; air-, escape-, feed-, injection-valve, etc. See also SAFETY-VALVE.
1659. Leak, Waterwks., 13. Of the Value or Suspiral. It will be also necessarie … to demonstrate the manner of the value of Copper which openeth itself by intervals.
1667. Phil. Trans., II. 447. A Square Woodden Bucket … on the ends of which are the moveable bottoms or Valves EE.
1702. Savery, Miner’s Friend, 68. Will not these Brass Valves … in your Engine speedily ware out?
1800. Vince, Hydrost., ix. (1806), 9. Each sucker has a valve opening upwards.
1839. R. S. Robinson, Naut. Steam Eng., 11. The pressure shuts the valve in the neck of the air vessel, and opens the valve in the piston.
1889. Welch, Text Bk. Naval Archit., 133. Self-acting or automatic valves are fitted where watertight bulkheads … are pierced for ventilation purposes.
fig. 1830. Gen. P. Thompson, Exerc. (1842), I. 295. The slightest degree of popular interference which can act as a valve to the great boiler, and prevent the whole from blowing up.
1847. De Quincey, Secr. Soc., Wks. 1863, VI. 236. There was a valve in reserve, by which your perplexity could escape.
7. attrib. and Comb. a. In sense 6, as valve-board, -box, casing, chest, engine, face, etc.; valve governor, lifter; valve-like, -shaped adjs.; also in collocations used attributively, as valve-guide stem, valve-rod end.
The number of attributive uses is very great, esp. in recent technical works.
1869. Eng. Mech., 24 Dec., 352/3. There is a board screwed down on the top of A. That is the *valve-board.
1885. C. G. W. Lock, Workshop Receipts, Ser. IV. 290/2. The valve-boards are next hinged on to the feeder-boards.
1797. Encycl. Brit. (ed. 3), XVII. 766/2. Above … is the seat of the lower steam valve, opening into the *valve box.
1869. Eng. Mech., 3 Dec., 282/2. Take the high pressure valves out of the valve-box.
1839. R. S. Robinson, Naut. Steam Eng., 44. The flange to which is bolted the *valve casing.
1887. D. A. Low, Machine Draw. (1892), 74. An elevation of the valve casing with the cover and the valve removed.
1839. R. S. Robinson, Naut. Steam Eng., 62. The blow-through pipe, terminating in a *valve chest.
1889. Welch, Text Bk. Naval Archit., xi. 124. In the former, a suction-box or valve chest V is fitted beneath the pump.
1797. J. Curr, Coal Viewer, 44. The plug floor in all the common engines falls 171/2 inches below the top of the boiler, and in the *valve engine it falls 2 feet 1 inch below.
1864. Webster, *Valve-face.
1887. D. A. Low, Machine Draw. (1892), 70. The angle which the valve face makes with its axis is generally 45°.
1842. Penny Cycl., XXII. 508/2. To bring the *valve-gear within … reach of the engineer.
1835. Ure, Philos. Manuf., 27. *Valve governors, shafts, and other gearing of mills.
1875. Knight, Dict. Mech., 2476/1. The *valve-guide stem has an end knob, by which its falling out is prevented.
1839. R. S. Robinson, Naut. Steam Eng., 97. The eccentric rod pulled backwards and forwards by means of the *valve lifter.
1851. S. P. Woodward, Mollusca (1856), 34. The in-coming and out-going currents … are kept apart by a *valve-like fringe.
1859. Semple, Diphtheria, 296. A valve-like sound or a peculiar hissing noise.
1836–41. Brande, Chem. (ed. 5), 524. A slender pipe, open at both ends, inserted into the *valve-plug.
1831–3. Encycl. Metrop. (1845), VIII. 187/1. In this engine the working the valves is effected by eccentrics … below the *valve rods.
1861. Sir W. Fairbairn, Iron, 123. To knock off the point of the trigger from the shoulder on the valve-rod.
1887. D. A. Low, Machine Draw. (1892), 119. Valve-rod end for a marine engine.
1841. Civil Eng. & Arch. Jrnl., IV. 379/2. H, the *valve-seat. Ibid. (1844), vii. 190/2. The next valve was composed of several triangular pieces, opening on leather joints, from the circumference of the *valve seating.
1879. St. George’s Hosp. Rep., IX. 365. Small *valve-shaped wound over outer side of fracture.
1844. Civil Engin. & Arch. Jrnl., VII. 192. It was quite clear the *valve-spindle must be of adequate strength.
1827. Faraday, Chem. Manip., xv. (1842), 373. Applying the mouth to the lower aperture of the *valve tube.
b. In sense 4, as valve-flap, lesion, segment.
Many others occur in recent medical works.
1879. St. George’s Hosp. Rep., IX. 433. The junction of two of the aortic valve-flaps.
1898. Allbutt’s Syst. Med., V. 952. A deformed valve segment must … be a strained segment. Ibid., 1024. In the remainder there was no valve-lesion.
c. Special Combs.: valve-shell, a gasteropod of the genus Valvata; valve-tailed bat (see quot.).
1851. Woodward, Mollusca, I. 140. Valvata,… Valve-shell.
1871. Cassell’s Nat. Hist., I. 316, note. The Valve-tailed Bat … is remarkable … for the presence of a curious horny case, composed of two parts, which covers the extremity of the tail.
