(כּוֹבִע or קוֹבָע kob, kob, περικεφαλαία), a military cap for the defense of the head in battle (1 Samuel Helmont, FRANCOIS MERCURE, baron VAN, was born at Vilvorde in 1618. In his youth he studied medicine, and applied himself especially to alchemy. He then joined a band of gypsies, with whom he traveled through part of Europe, but was arrested in Italy in 1662, and cast into the dungeons of the Inquisition. In 1663, being liberated, he went to Sulzbach, where he worked with Knorr of Rosenroth at the Kabbala denudata. He published, about the same time, a work on the alphabet of the primitive tongue, i.e. Hebrew (Sulzbach, 1667, 12mo), which, according to him, is so natural that every letter expresses merely the position of the lips while pronouncing it: he pretended to teach the deaf and dumb to articulate all the sounds of his alphabet at first sight. He believed in the transmigration of souls, the universal remedy, and the philosopher's stone. He traveled afterwards through England, and returned through Hanover to Berlin, in a suburb of which city he died in 1699 (Moreri says he died at Cologne; Toppens, in Switzerland; Wachter, at Emmerich, in Dec. 1698). Leibnitz wrote on him the following epitaph:
"Nil patre inferior, jacet hic Helmontius alter, Qui junusxi varias mentis et artis opes: Per quem Pythagoras et cabbala sacra revixit Elcensque, parat qui sua cuncta sibi."
Besides the alphabet above mentioned, he wrote Opuscula Philosophica, quibus continentur principia philosophie antiquissim et recentissimae, etc. (Amsterd. 1690, 12mo): — Quaedam prcemeditatae et consideratce Cogitationes super quatuor priora capita libri primi Moisis, Genesis nominati (Amst. 1697, 8vo): — De Attributis divinis, etc. See Adelung, Hist. de la Folie humaine, 4:294-323 Moreri, Grand Dict. hist.; Hoefer, Nouv. Biog. Géneralé, 23, 864.