Deceased Members — Professor Mohs. 537 



to which he gave the name of Zoogene ; and he also supposed that 

 he found the same substance in the thermal waters of Ischia, and in 

 waters produced by the condensation of the. steam disengaged from 

 Vesuvius. A similar mucous substance, in the thermal sulphureous 

 waters of Roussillon, was supposed by Professor Anglada, of Mont- 

 pelier, to be a chemical product, from elements held in solution by 

 the waters at the time they issued from the earth, and deposited 

 by them in a flocculent form when they come in contact with the 

 air. De Saussure, however, Decandolle, Dillwyn, and Daubeny*, 

 founding their opinions on the structure it exhibits under the micro- 

 scope, refer this gelatinous substance to minute Confervas ; but the 

 more recent discovery, by Ehrenberg, of infusorial animals in the 

 warm springs of Bohemia, gives some probability to the supposition 

 that these may be mixed with Confervas in the so-called zoogene 

 of Gimbernat. The decomposition either of Confervas or of In- 

 fusoria would afford the azote found in zoogene ; but their presence 

 would transfer the origin of this organic substance from simple che- 

 mical agency to the instrumentality of organic life. On quitting 

 Naples, in 1820, he retired to Switzerland, where he fell into bad 

 health and reduced circumstances, and died at Geneva in 

 1839f. 



Frederick Mohs, Professor of Mineralogy in Vienna, was born 

 at Gernrode, in the Harz Mountains, about 1770. He lost his 

 father, a merchant, very early, and was expected to succeed him in 

 the business ; but his predilections for science, particularly for ma- 

 thematics, had marked him out for higher destinies. 



He began his studies, 1796-98, at Halle, and continued them in 

 the mining institution at Freyberg. 



We find him in 1802 at Vienna, occupied in describing the mi- 

 neral cabinet of the banker Von der Null, where he first conceived 

 those views which he afterwards developed in his system of mine- 

 ralogy. 



His fondness for geology and the art of mining induced him to 

 visit Styria, Saltzburg, Carinthia, Carniola, Hungary and Transyl- 

 vania, &c, and he received from the Austrian Government, in 1810, 

 a commission to examine those parts of Passau, Austria, and Bohe- 

 mia, where porcelain clay is found. 



Having thus attracted the notice of the Archduke John, and un- 

 dertaken a journey to Styria in 1811, he was nominated Professor 

 of Mineralogy in the Johanneum, at Gratz. 



In 1818 he visited England with Count Breiiner, who had been 

 his pupil at Gratz ; his conferences at Edinburgh with Jameson, 

 whom he had known at Freyberg, made a strong impression on 

 the Professor, in favour of what he called the " natural-history- 

 system " of mineralogy, which he in part adopted, and first made 



* On Organic Matter in Sulphureous Springs, Linn. Trans., London, 

 vol. xvi. 1833. 



f A short notice on Sulphate of Soda is published by Gimbernat in our 

 Transactions, vol, ii., second series, p. 331. 



