Metamorphism in the Mineral Kingdom. 267 



was found to be present in the skull of the Mandtus senega- 

 lensis, which inhabits the rivers at Old Calabar. 



III. Historical Review of the State of our Knowledge respecting Meta- 

 morphism in the Mineral Kingdom, with special regard to certain 

 recent Researches. By John S. Livingston, Esq. 



Mr Livingston stated, that within late years great addi- 

 tions had been made by the labours of chemical geologists 

 to our knowledge of the more recondite geological pheno- 

 mena. To these additions he wished to direct the attention 

 of the Society, as they seemed in this country to have, in a 

 great measure, escaped notice. After expressing his opinion 

 that, if we are to make any advances in our knowledge of 

 the deep-seated causes of metamorphic changes, it must be 

 brought about by introducing into the methods of geological 

 research much more of the experimental than had hitherto 

 been considered necessary, he rapidly sketched the progress 

 of inquiry into metamorphism. Every year was enabling us 

 more and more to imitate the mineral productions that occur 

 in nature, though we cannot reproduce all the conditions 

 under which they were formed. What the influence of the 

 long lapse of ages might have been, must of course ever 

 remain an insoluble problem. After passing under review 

 the opinions of Hutton, Mr Livingston referred to the expe- 

 riments of Sir James Hall, but especially to his having 

 succeeded in producing a crystalline marble, by placing 

 powdered calc spar in a gun-barrel hermetically sealed, and 

 exposing it to a high temperature, — an experiment that had 

 been recently impugned by Gunstav Kose, but on insufficient 

 grounds. Keference was then made to the processes adopted 

 by Berthier, H. Daville, and Caron, for artificially producing 

 minerals by fusion alone, and especially to the production 

 of corundum by Ebelman. But the most important re- 

 sults were obtained when Senarmont, by experimenting on 

 minerals with water at high temperatures, and under enor- 

 mous pressures, produced crystalline quartz, spathic iron, 

 sulphate of baryta, and sulphide of antimony. Daubree in- 

 1857 had, by using a temperature of 572° Fahr., converted 

 wood into anthracite ; and Baroulier in 1858 obtained coal 

 vol. it. 2 M 



