[ad. med.L. strātificātiōnem, n. of action f. strātificāre: see STRATIFY v. and -FICATION. Cf. F. stratification (1656 in Hatz.-Darm.).]
† 1. The action of depositing something in layers; spec. (see quots.). Obs.
1617. Woodall, Surg. Mate (1639), 274. Stratification, or stratum superstratum well knowne to Chymists, and used in cementation, is strewing of corroding powder, or the like, upon plates of metall by course. Ibid., 266. Stratifigations [sic].
1669. trans. Beguinus’ Tyroc. Chym., 25. Stratification is a corrosion by corrosive powders. It is thus made, [etc.].
1669. Rowland, Schroder’s Chym. Disp., I. xiv. 21. Stratification in Beguin comprehends the whole Art of Calcination, by which the Plates are made brittle, this they say is Cæmenting.
1704. J. Harris, Lex. Techn., I. Stratification, or stratum super stratum, as the Chymists call it, is putting different Matters Bed upon Bed, or one layer upon another, in a Crucible in order to Calcine a Metal or Mineral.
1787. R. Watson, Chem. Ess., V. 251. Copper combined with sulphur by stratification and cementation…. Æs ustum.
1815. J. Smith, Panorama Sci. & Art, II. 301. Stratification, an operation in which bodies are placed alternately in layers, in order that they may act upon each other when heat is applied to them.
1882. Encycl. Brit., XIV. 385/1. It was formerly the practice in England … to tan by the process of stratification, for which purpose a bed of bark is made…; upon this is laid the hide, then bark, then a hide, and so on.
2. The formation, by natural process, of strata or layers one above the other; the fact or state of existing in the form of strata, stratified condition; also, the manner in which something is stratified.
a. Geol. The formation of strata in portions of the crust of the earth by successive deposits of sedimentary matter; the manner in which a portion of the crust of the earth is stratified.
1795. J. Hutton, Theory Earth, II. ix. II. 307. This summit is of solid granite, a mass in which there is no stratification.
1796. Kirwan, Elem. Min. (ed. 2), I. 420. A total absence of stratification near the crater.
1802. Playfair, Illustr. Huttonian Theory, 500. Thus by the waste and subsequent stratification of the land the direction of gravity is continually altered.
1830. Lyell, Princ. Geol., I. 203. The planes of stratification are perfectly parallel.
1838. Poe, A. Gordon Pym, xviii. Wks. 1865, IV. 146. The very rocks were novel in their mass, their color, and their stratification.
1851. Richardson, Geol. (1855), 135. There are three distinct forms of structure frequently present in rocks of this nature: stratification, joints, and slaty cleavage.
1878. A. C. Ramsay, Phys. Geog., iv. 38. I have shown how aqueous rocks may generally be known by their stratification.
b. concr. A stratum produced by this process.
1808. W. Richardson, in Phil. Trans., XCVIII. 220. Regular stratifications on the summits of hills and mountains, have been long a stumbling block to theorists.
1822. J. Parkinson, Outl. Oryctol., 267. The matrix of these fossils is evidently a portion of the same stratification which occurs at Pappenheim.
c. Biol. and Path. The thickening of a tissue by the deposition or growth of successive thin layers.
1875. trans. De Bary, in Jrnl. Bot., Oct., 301. In Chara fragilis,… this membrane shows a copious tender stratification after the carbonate of lime has been dissolved.
1876. trans. Wagner’s Gen. Pathol., 200. The form, color, and stratification of the impacted piece.
1880. Bessey, Bot., 32. During the increase of the cell-wall in thickness, an appearance of stratification arises in it.
1887. T. W. Shore, Elem. Biol. Vegetable, 10. Observe … Stratification of the cuticle, i. e. the appearance of lines in it, parallel to the surface of the section.
1899. Cagney, trans. Jaksch’s Clin. Diagn., iv. (ed. 4), 115. In some diseases, as in abscess and gangrene of the lung there is marked stratification of its [i.e., the sputum’s] parts.
d. Electr. The striated appearance assumed by an electric discharge passing through a highly rarefied gas.
1856. T. R. Robinson, in Proc. R. Irish Acad., VI. 429. When a Leyden jar (each coating about a foot) was connected with the terminals, the stratification was well seen in each direction of the current.
1858. J. P. Gassiot, in Phil. Trans., 1. The phenomenon of stratifications in the discharge in vacuo were subsequently observed in Paris by M. Rubmkorff.
1866. R. M. Ferguson, Electr. (1870), 193. The cause of this stratification is as yet a matter of speculation.
e. transf. and fig., chiefly with reference to the geological use.
1860. Maury, Phys. Geog. (Low), xxii. § 885. Let us, in imagination, divide these depths … into any number of stratifications or layers of equal thickness.
1862. Burton, Bk. Hunter (1863), 113. The library is the great intellectual stratification in which the literary investigator works.
1879. Baring-Gould, Germany, I. 2. The stratification of the German classes, and of the aristocracy, is most peculiar.
1889. A. Sidgwick, in Jrnl. Educ., Feb., 117. That there is not a chance of saving much time by improved methods and proper stratification.
1910. D. G. Hogarth, in Encycl. Brit., I. 248/2. (Aegean Civiliz.), By exact observation of stratification, eight more periods have been distinguished by the explorer of Cnossus.
3. attrib.
1884. A. Geikie, in Nature, 13 Nov., 30/1. These thrust-planes … could not be distinguished from ordinary stratification-planes.
