254 EXPERIMENTS ON METAMORPHISM AND 



In England — Sir James Mackenzie, Jameson, Conybeare, Bucliland, 

 Greenough, Sir R. Murchisou,* Sedgwick, Sir H, de la Beche,t John 

 Phillips, I Colonel Portloch, Doubney, Berger, Poulett, Scrope, Hens- 

 low, Ramsay. 



In Germany — Humboldt, Naumaim,§ de Leonhard, Mitscherlich, 

 Haussmann. W. Haidinger, ;| B. Cotta,l G. Rose, Abich, d'Alberti, de 

 Morlot, Blum,^* Credner. 



In Switzerland and Italy — Escher de la Linth,tt de Charpentier, 

 Lard)^, de Collegn,|| de la Marmora, A. Favre,^§ de Marignac, Theo- 

 bald. 



In the Scandinavian peninsula — A. Erdmann, 



In America — Rogers, Hitchcock, Whitney, Sir W. Logan, Sterry 

 Hunt. 



CHAPTER A^III. 



HISTORY OF SYNTHETICAL EXPERIMENTS, TENDING TO ELUCIDATE THE 

 QUESTION OF METAMORPHISM. 



The progress which we have just sketched has cost more effort than 

 we could at present suppose, for there was scarcely any other guide 

 than purely geological facts, elucidated by analogy and induction. 

 We should have reposed in views of necessity very vague, if synthet- 

 ical experiment had not followed direct observation, to substantiate 

 and complete it. 



It has seemed best to me to enumerate by themselves, and with some 

 details, the principal attempts which have been made up to this time 

 to imitate minerals and rocks artificially. They throw light on the dif- 

 ferent processes which may have been brought to bear in the very various 

 reactions of nature ; besides, that these are the first steps in a method 

 which appears destined to reveal very important facts for the history 

 of formations and for metamorphism. Leibnitz, it is true, had pro- 

 foundly appreciated the utility of experiments for the interpretation 

 of the formation of strata, and compared, as far as he was able, the 



* Tbe works of Sir R. Murchison on the silurian formations of England, on the Alps, 

 and the Ural, present numerous and important examples of metamorphism. 



-j-Sir H. de la Beche, in his The>retical Manual, his Art of Observing, his Geological Re- 

 searches, and his Geological Report on Chniwall and Devon, has publishfd a great number of 

 judicious and ingenious observations on metamorphism, as on all other subjects of geology. 



:}: Among the works of Mr. J. Phillips, we must here make mention of a report on 

 schistose cleavage, inserted in the memoirs of the British Association. 



§ Besides his observations made in J^axony and Norway, Naumann has treated metamor- 

 phism in detail in his excellent work on Geognosy. 



II Haidinger proposes to distinguish anogenom and catogeriom metamorphism, according as 

 they occur near the surface or at a great depth. 



*^\ Especially in the Qeohgische Briefe aus den Alperi. 



•'*In his studies on the pseudomorphs, Blum has described many facts akin to metamor- 

 phism. 



ft Numerous observations made in Switzerland with Studer. 



f J5ur le mttamorpkisme des terrains de sediment. Bordeaux ; 1812. 



§§A^o<jce stir la geologic du Tyrol alkmand ; 184-9. 



