*

MANGANESE. 379

the value was enhanced in proportion to that approxima-tion.

Attempts have been made to assign a period for this dis-covery, but unsuccessfully; the nearest approach is, that itmust have been anterior to the days of Pliny ; as he oftenspeaks of it in his writings, under the designation of magnet,as an ingredient proper for this purpose; it is also observed,that the proper distinction between manganese and themagnet itself, was not made till since the days of Agricolaand Kircher.

In another passage in Pliny , he observes, alabandicvsflows in the lire, and is fused in the glass-houses. By thatterm, he nevertheless appears to understand a kind of mar-ble; alsd as such Isidorus seems to notice it; he, the lastauthor , repeats the word more than once. As a calcareousearth, it might be added to promote the fusion of the sand.Cainillus Leonardos, it is said, considered the alabandicusas manganese, which admirably assimilates with enamel:and although we possess no evidence of its anterior applica-tion, in that kind of painting, it is confidently alleged byseveral eminent modern antiquaries, that those beautifulspecimens observed upon vases of Grecian workmanship,and all the splendid colours there displayed are the produceof manganese; and likewise those so surprisingly brilliant inthe antique lamps of that country.

The celebrated Count C'aylus , + whose experience in mat-ters of this nature is confessed, at the time the votaries oftaste and admirers of antiquity are happy in acknowledgingthe benefits which the modern world have derived from hissuccessful inquiries; and also Genssane , 4 5 as we understand,have not scrupled to avow that the Greek enamel, and alsothe colour in their lamps, were produced by the agency ofmanganese.

That great regenerator of the practice of ancient physicto the moderns, the Arabian, Avicenna , 6 whose name willstand for system itself, has described manganese so clearly,so completely and ably defined it, and not only as to theapparent character, but the genuine nature of this mineral,that he has left it to others only to transcribe what he has

4 Recueil d'Antiquites, i. p. 86.

5 Traite de la Foute des mines par le feu du Charbon de Terre, Paris , 1770,2 vol. 4to. i. p. xv.

6 Canon Medicina?, lib. ii. tTact. 2, cap. 470, de Magnete. In the edition, Vc*nctiis apud Iuntas, 1608, fed. i. p. 336 and 357, he has made so complete a dis-tinction between it and the magnet, that he treats of those substances in separate.sections.