[Cf. Du. weerglas, Da. veirglas, Sw. väderglas, G. wetterglas.]
† 1. A kind of thermometer, used to ascertain the temperature of the air, and also to prognosticate changes in the weather. Obs.
It consisted in its simplest form of an upright tube filled with water, terminating at the top in a bulb containing rarefied air. The water sank or rose in the tube as the air in the bulb expanded or contracted.
1626. Bacon, Sylva, § 27. Cold … doth manifestly Condense; As we see in the Contracting of the Aire in the Weather-Glasse.
1634. J. B[ate], Myst. Nat. & Art, 28. A Weather-glasse is a structure of, at the least, two glasses, sometimes of three, foure, or more, as occasion serueth, inclosing a quantity of water, and a portion of ayre proportionable, by whose condensation or rarifaction the included water is subject unto a continuall motion, either upward or downward; by which motion of the water is commonly foreshewn the state, change, and alteration of the weather.
a. 1643. Suckling, Brennoralt, II. i. His colour … sanke down As water in a weather-glasse Prest by a warme hand.
1669. Worlidge, Syst. Agric., 257. For the true discovery of the nature and temper of the Air, as to its density or rarity, we have not met with a more certain or compleat invention than the Weather-glass. Ibid., 259. The Weather-glass or Thermoscope.
1670. Dryden, 1st Pt. Conq. Granada, IV. ii. (1672), 36. As in some wether-glass my Love I hold; Which falls or rises with the heat or cold.
1694. Phil. Trans., XVIII. 205. A tender Weather-Glass or Thermometer. Ibid. (1720), XXXI. 117. Two Thermometers, the one the common seal’d Weather-glass, having no Communication with the outward Air, wherein the temper as to Heat and Cold was shown by the swelling or shrinking of the included Spirit.
2. A barometer.
1695. Lond. Gaz., No. 3103/4. A Portable Barometer, or Weather-Glass.
1710. Addison, Tatler, No. 220, ¶ 3. Toricellius, the Inventor of the common Weather Glass.
1758. Johnson, Idler, No. 33, ¶ 2. Weather rainy. Consulted my weather-glass.
1848. Clough, Bothie, II. 17. The weather-glass, say they, is rising.
1885. New Bk. Sports, 23. There is no trusting the weather-glass among the Highland hills.
3. fig.
1654. R. Whitlock, Ζωοτομια, 276. I shall onely refer you to the Polititians Weather-glasse, whereby he not onely foreseeth (but discerneth aright when fallen) the unseasonable weather of his respective Place he liveth in.
1681. D’Urfey, Progr. Honesty, xiv. 32. His Bone’s his Weather-Glass, and his Back Is his perpetual Almanack.
1742. H. Walpole, Lett. to Mann, 24 June. My uncle, who is my political weather-glass, and whose quicksilver rises and falls with the least variation of parliamentary weather.
1748. Richardson, Clarissa (1768), VIII. 180. When the weather-glass of my pride got up again, I found I had gone too far to recede.
1864. G. A. Lawrence, Maurice Dering, II. 80. Besides, I’m not at all sure that he was losing heavily: his own face is a bad weather-glass.
4. Poor Man’s, or Shepherd’s, Weather-glass: a name for the scarlet pimpernel, Anagallis arvensis, from its closing its flowers before rain.
1827, 1872. [see SHEPHERD sb. 7 d].
1836. J. T. Mackay, Flora Hibern., I. 194. Common Pimpernel, or Poor Man’s Weatherglass.
