a. Also 8 vitrious. [f. L. vitre-us of glass, glassy, bright, etc., f. vitrum glass, VITRUM: see -OUS. Cf. F. vitreux, -euse.]
1. Of or belonging to, consisting or composed of, glass; of the nature of glass; glassy.
1646. Sir T. Browne, Pseud. Ep., II. i. 51. Calcination or reducing it by Arte, into a subtile powder, by which way and a vitreous commixture, glasses are sometime made hereof.
1711. Shaftesb., Charac., III. 15. The tumid Bladder bounds at every Kick, bursts the withstanding, Casements, the Chassys, Lanterns, and all the brittle vitrious Ware.
1784. Cowper, Task, V. 161. Mirrour needed none Where all was vitreous.
1791. W. Hamilton, Berthollet’s Dyeing, II. II. IV. iv. 275. A vessel of earthenware with a vitreous coat.
1827. Faraday, Chem. Manip., vii. (1842), 224. Glass would then be easily acted upon, and … the product obtained would not be pure, but a combination, with part of the vitreous matter.
1852. Dickens, Repr. P., Plated Article. Of course, you saw the glaze—composed of various vitreous materials—laid over every article.
1882. Geikie, Text-bk. Geol., II. II. § 4. 105. The final stiffening of a vitreous mass into solid stone.
fig. 1836. New Monthly Mag., XLVI. 206. He had left the vitreous and mercurial clime of France … for the voluptuous and indolent air of Italy.
b. Geol. and Min. Resembling glass in brittleness, hardness, luster, and mode of cleavage.
1774. in Forster, Voy. (1777), I. 587. Some of them carried arms,… which were headed with a black vitreous lava.
1796. Kirwan, Elem. Min. (ed. 2), I. 409. All real lavas except those of the vitreous kind affect the magnetic needle, unless the iron they contain be much oxygenated.
1811. Pinkerton, Petral., I. 45. There are … evidences of a vitreous lava in one of the isles of Faroe.
1849. Murchison, Siluria, iii. 38. It is often intersected by veins of vitreous quartz.
1855. Orr’s Circ. Sci., Geol., etc., 498. Redruthite.—Vitreous Copper. Prismatic Copper Glance.
1868. Watts, Dict. Chem., V. 306. Vitreous Silver. Native argentic sulphide.
1882. Geikie, Text-bk. Geol., II. II. § 4. 100. Crystallites … seem to be earlier or peculiar forms of crystallization developed … in many vitreous rocks.
c. Chem. Resembling glass in composition.
1800. trans. Lagrange’s Chem., I. 369. There remains in the retort a vitreous mass,… which is very pure arsenic acid.
1826. Henry, Elem. Chem., I. 363. Equal parts of potassium and very pure and vitreous boracic acid were put into a copper tube.
1866. Roscoe, Elem. Chem., xiv. 122. Like sulphur, it is capable of existing in various allotropic modifications, one of which is crystalline, the other vitreous.
d. Anat. and Zool. (See quots.)
(a) 1858. Humphry, Hum. Skeleton, 206. The separation of the outer and inner tables of the skull by the intervening diplöe…. The inner, or ‘vitreous’ table, which is the most dense.
1866. Chambers’s Encycl., VIII. 759. An inner dense, brittle, and somewhat glass-like layer, known as the vitreous table or layer.
(b) 1873. C. W. Thomson, Depths of Sea, vii. 422. When the first specimen of Hyalonema was brought home, the other vitreous sponges which approach it so closely in all essential points of structure were unknown.
1879. Carpenter, in Encycl. Brit., IX. 378/2. The Vitreous Foraminifera may be grouped into three families. Ibid., 385/1. The material of their ‘porcellanous’ or ‘vitreous’ skeletons.
1896. trans. Boas’ Text Bk. Zool., 121. Vitreous sponges (Hexactinellidæ) are silicious forms, characterised by the striking beauty of the skeleton, which is like spun-glass.
2. † a. Med. Of phlegm: Having the thick viscid consistency of molten glass. Obs.
1661. Lovell, Hist. Anim. & Min., 437. Of phlegme, if salt, from thirst…. If vitreous, from fixed paine.
1684. trans. Bonet’s Merc. Compit., III. 98. She voided much vitreous phlegm and bilious humours.
1707. Floyer, Physic. Pulse-Watch, 75. A moderate degree of Cold produces a sweet Phlegm … and the greatest an Acerbe vitrious slime towards the coldest time of Winter.
b. Vitreous humo(u)r (or body), the transparent gelatinous substance occupying the posterior and larger part of the eyeball. † Vitreous tunicle (see quot. 1704).
1663. Boyle, Usef. Exp. Nat. Philos., I. 96. We have sometimes … speedily frozen Eyes, and thereby have turn’d the Vitreous humor into very numerous and Diaphanous Films.
1676. Phil. Trans., XI. 747. As to the Vitreous humor, he judges it to be of that nature, that being once lost, it can never be repaired.
1704. J. Harris, Lex. Techn., I. Vitrious Tunicle, a thin Film, or Coat, which is said to separate the Glassie Humour from the Chrystalline.
1710. J. Clarke, trans. Rohault’s Nat. Philos. (1729), I. 237. The Vitreous Humour … being one of the most transparent Things that we know of in the World.
1793. Phil. Trans., LXXXIII. 175. Its elasticity will assist the cellular texture of the vitreous humour … in restoring the indolent form.
1831. R. Knox, Cloquet’s Anat., 559. The Vitreous Body is a soft, perfectly transparent, tremulous mass, occupying the three posterior fourths of the cavity of the ball of the eye.
1877. M. Foster, Physiol., III. i. (1878), 398. The rays of light traverse in succession the cornea, the aqueous humour, the lens and the vitreous humour.
c. ellipt. as sb. = prec.
1869. G. Lawson, Dis. Eye (1874), 144. He has succeeded in thus extracting the lens without the loss of any vitreous.
1879. St. George’s Hosp. Rep., IX. 479. A quantity of the thin fluid vitreous escaped.
3. Vitreous electricity, positive electricity obtained from glass by friction.
1759. Phil. Trans., LI. 308. Experiments … respecting the vitreous and resinous electricities, as they are called.
1799. [see ELECTRICITY 1 b].
1840. Carlyle, Heroes, i. (1904), 18. Thunder was not then mere Electricity, vitreous or resinous.
1860. Emerson, Cond. Life, Wealth, Wks. (Bohn), II. 357. The genius of reading and of gardening are antagonistic, like resinous and vitreous electricity.
1879. Proctor, Pleas. Ways Sc., xi. 238. If glass is briskly rubbed with silk it becomes charged … with positive electricity, formerly called vitreous electricity for this reason.
4. Resembling that of glass; characteristic of glass.
1811. A. T. Thomson, Lond. Disp. (1818), 196. The tears are … brittle, and break with a vitreous fracture.
1841. Brande, Chem. (ed. 5), 130. This change from the vitreous to the crystalline state sometimes takes place suddenly.
1854. Ronalds & Richardson, Chem. Technol. (ed. 2), I. 42. They form a … perfectly black mass,… generally possessing a fatty or vitreous lustre.
1863. A. C. Ramsay, Phys. Geog., i. (1878), 20. Modern lavas have often a vitreous structure (glassy) such as obsidian.
b. Having the color or appearance of glass.
1874. R. Buchanan, Pan, Poet. Wks. I. 90. What time the pallid sickle wax’d Blue-edged and vitreous o’er the black’ning West. Ibid. (1882), Annan Water, i. The vitreous rays of the moon began playing on the window panes.
1900. B. D. Jackson, Gloss. Bot. Terms, Vitreous,… transparent, hyaline; formerly used for the light green of glass.
5. Comb., as vitreous-like, -shelled adj.
1879. Carpenter, in Encycl. Brit., IX. 378/1. The vitreous-shelled Feraminifera constitute the most elevated division of the group.
1902. Westm. Gaz., 22 Sept., 6/3. Some of the finer wares will break showing a vitreous-like substance.
Hence Vitreousness.
1727. Bailey (Vol. II.), and later Dicts.
1883. Solon, Art Old Eng. Potter, 73. The Crouch-ware is of a dense paste; if not quite so hard as the red porcelain, it is because the ferric oxide contained in the latter increases its vitreousness.
