[ad. L. subsīdentia sediment, f. subsīdĕre to SUBSIDE: see -ENCE. Cf. It. sussidenza sediment.]
1. A sediment, precipitate. ? Obs.
1646. Sir T. Browne, Pseud. Ep., 92. A Chalky earth, which … steeped in water, affoordeth a cream … on the top, and a grosse subsidence at the bottome.
1650. Vaughan, Anthroposophia, 15. The Earth was an impure, Sulphureous subsidence, or Caput mortuum of the Creation.
1847. Clarke, in Jrnl. R. Agric. Soc., VIII. I. 109. The soil of the whole is the subsidence of a muddy water.
1890. Gould, New Med. Dict., Subsidence,… in pharmacy, the sediment falling from a liquid.
2. The settling (of solid or heavy things) to the bottom, formation of sediment, precipitation.
1656. Blount, Glossogr., Subsidence, a resting or setling in the bottom.
1696. Whiston, Th. Earth, III. (1722), 278. The same Law … was also observ’d in the subsidence of the Shells of Fishes.
1765. Museum Rust., IV. 98. What I have written on the subsidence of chalk, and the simple method of recovering that almost-lost manure.
1799. Monthly Rev., XXX. 150. A force of subsidence, the natural consequence of gravity,… has produced similar effects.
1800. Henry, Epit. Chem. (1808), 125. Separate the liquid part by filtration or by subsidence.
1857. Miller, Elem. Chem., Org. (1862), iv. § 1. 259. The clear oil is afterwards agitated…, again clarified by subsidence [etc.].
3. The sinking (of liquids) to a normal or lower level; also, a fall in the level of ground.
1669. Boyle, Contn. New Exp., xix. 62. The Quick-silver that before stood at 29 inches … would fall so low as to rest at 9 or 10 inches, (for once I measur’d the Subsidence beneath its former Elevation).
1837. Syd. Smith, Wks. (1850), 641. One of those Shem-Ham-and-Japhet buggies—made on Mount Ararat soon after the subsidence of the waters.
1839. G. Bird, Nat. Philos., 104. The subsidence of mercury in the barometer, as we ascend mountains … affords valuable data for calculating their vertical height.
1863. Hawthorne, Our Old Home (1879), 104. The country … is a succession of the gentlest swells and subsidences.
1865. Livingstone, Zambesi, xxi. 429. Snags … left in the channel on the sudden subsidence of the water.
b. A fall in rhythm or accent.
1824. Landor, Imag. Conv., Æschines & Phocion, Wks. 1853, I. 26/2. Concentrated are his arguments,… easy the swell and subsidence of his periods, his dialect purely attic.
1851. Hawthorne, Ho. Sev. Gables, x. He delighted in the swell and subsidence of the rhythm, and the happily-recurring rhyme.
4. A sinking into inactivity or quiescence.
a. of feelings, of a disturbance, of the attacks of a disease, etc.
1754. Warburton, Serm., 27 Oct., Wks. 1783, V. 519. The mind … being, by the subdual or subsidence of the more violent passions, now become attentive to, and sensible of, the soft and gentle impressions of tranquillity.
1847. Dickens, Haunted Man, ii. 70. A decided subsidence of her animosity.
1864. Lowell, Fireside Trav., 256. So these people burst out … into a noise and fury…. And the subsidence is as sudden.
1890. Gould, New Med. Dict. Subsidence,… in pathology, the gradual cessation and disappearance of an attack of disease.
b. Of physical phenomena or actions.
1731. Arbuthnot, Aliments, II. ii. (1735), 29. The alternate Motion of those Air-Bladders, whose Surfaces are by turns freed from mutual Contact, and by a sudden Subsidence meet again by the ingress and egress of the Air.
18[?]. Edin. Rev. (Seager). Subsidence of waves.
1860. Tyndall, Glac., I. 81. The subsidence of this action [throbbing] was always the signal for further advance.
1864. Lowell, Fireside Trav., 292. We awaited her subsidence as that of a shower.
1879. Cassell’s Techn. Educ., I. 215. A second … fermentation takes place…; its subsidence diminishes the bulk of the wine.
c. Sinking into decline or decay.
1856. Merivale, Rom. Emp. xxxiii. (1865), IV. 67. It was about the period of the Gracchi that this subsidence of the old aristocracy of birth began first to be remarked.
5. (orig. Geol.) A gradual lowering or settling down of a portion of the earth due to dynamic causes, mining operations, or the like.
1802. Playfair, Illustr. Hutton. Th., 449. Though a local subsidence, or settling of the ground, could hardly account for this change,… yet a subsidence that has extended to a great tract … will agree very well with the appearances.
1854. Murchison, Siluria, vi. 131. The rock is … subject to slides or subsidences.
1856. Page, Adv. Text-bk. Geol., ii. 39. Subsidences occasioned by earthquake and volcanic convulsions.
1912. Standard, 20 Sept., 6/4. Streets and buildings … are being damaged by subsidences due to disused underground workings.
transf. 1861. Morning Post, 27 Nov. They reached the door, but found it fixed by the subsidence of the walls.
6. attrib., applied to vessels in which liquids are put in order to precipitate their suspended solid matter, as subsidence reservoir, vat.
1858. Simmonds, Dict. Trade, Subsidence-vat, a dyer’s settling-vat.
1892. Pall Mall Gaz., 9 Sept., 2/1. All the companies supplying river water … have subsidence reservoirs, into which the water is first turned for the purpose of allowing such of the suspended solid matter as will to settle.
