pyrognostics (pirog nos tiks)

[Pl. of pyrog nostic (see -ics ).] Those properties of a mineral which it exhibits when heated, alone or with fluxes, in the blowpipe-flame or in the flame of a Bunsen burner, as the fusibility, intumescence, or other phenomena of fusion, flame-coloration, etc. pyrography (pi-rog'ra-fi), n. [ Pyrogravure is a new method of engraving in black, reddish brown, bister, etc., by the use of a red hot metallic point. Sci . Amer ., N. S., LVIII. 353. pyro heliometer (pi-rō-hê-li-om'e-tėr), n. Same as pyrheliometer. Pyrola (pir'ō-lä), n. [NL. (Tournefort, 1700), so called from the resemblance of the shining leaves to those of the pear-tree; prop. Pirola; dim. of L. pir us, improp. pyrus, a pear-tree: see Pyrus.] 1. A genus of dicotyledonous plants of the order Ericaccæ, the heath family, type of the tribe Pyroleæ, characterized by racemed flowers with five converging petals, ten stamens with peculiar four-celled inverted anthers opening by pores, and a capsule opening from the base upward, with cobwebby margins. The 16 species are natives of the northern hemisphere, including 8 in the United States. They are smooth perennial herbs, sending out subterranean runners, and bearing radical or alternate long-stalked evergreen leaves, commonly entire and rounded, and an erect scape of bracted nodding flowers, which are white, yellowish, rose-colored, or purple. Several species are known in England and among American writers as wintergreen or false winter green. P. rotund i folia, the larger wintergreen, is the most conspicuous species, a plant of both hemispheres, with thickish veiny round leaves, and commonly pure-white flowers, the stalk 6 to 12 inches high. It has been called Indian lettuce and canker - lettuce. P. elliptic a, a smaller American plant with thin elliptical leaves, is called shin leaf, a name also extended to the genus. flowered pyrola, Moneses grandiflora, a plant once included in the genus Pyrola. electricity is used to include also the phenomena of thermoelectricity, which, however, are totally different in char acter.