ANEMOSCOPE

, is sometimes used to denote a machine invented to foretell the changes of the wind, or weather; and sometimes for an instrument shewing by an index what the present direction of the wind is. Of this latter sort, it seems, was that used by the ancients, and described by Vitruvius; and we have many of them at present in large or public buildings, where an index withinside a room or hall, points to the name of the quarter from whence the wind blows without; which is simply effected by connecting an index to the lower end of the spindle of a weather-cock. |

It has been observed that hygroscopes made of catgut, or such like, prove very good anemoscopes; seldom failing, by the turning of the index, to foretell the shifting of the wind. See accounts of two different anemoscopes; one by Mr. Pickering, vol. 43 Philos. Trans. the other by Mr. B. Martin, vol. 2 of his Philos. Britan.

Otto Gueric also gave the title anemoscope to a machine invented by him to foretell the change of the weather, as to rain and fair. It consisted of the small wooden figure of a man, which rose and fell in a glass tube, as the atmosphere was more or less heavy. Which was only an application of the common barometer, as shewn by M. Couriers in the Acta Eruditorum for 1684.