MINERALIZED AND METHYLOSED ROCKS. 29 



Notwithstanding the weight of authority on the side of 

 Vulcanism, Sterry Hunt maintains what he calls a " novel 

 doctrine," but which seems to be similar to the one taught by 

 Werner, and accepted to some extent by DelaBeche and others, 

 that the vast masses of ancient crystalline rocks known as 

 " Azoic/' ' ' Fundamental/' " Laurentian," " Eozoic," and 

 <( Archaean/' have been " directly deposited as chemical preci- 

 pitates from the seas of the time " * ; to be particular, that the 

 Canadian Archseans, comprising granitoid gneisses, syenites, 

 chlorite-, talc-, mica-, and hornblende- schists, and ophites, have 

 had their component minerals (steatite, serpentine, talc, chlorite, 

 phlogopite, augite, hornblende, orthoclase, labradorite, quartz, 

 epidote, and other species f) " formed, not by subsequent meta- 

 morphism in deeply buried sediments, but by reactions " J, " by 

 a crystallization and molecular rearrangement of chemically 

 formed silicates, generated by chemical processes in waters at 

 the earth's surface " . 



As our reasons have been given elsewhere for decidedly 

 rejecting this doctrine, it being altogether unsupported by ac- 

 ceptable evidences ||, there is no necessity for us to do more on 



* Canadian Naturalist, n. s., vol. iii. p. 125 (1860). 



t As hemithrenes are Archaean rocks, culcite, inieniite, and some other 

 mineral carbonates ought to be added to the list. 



| Quart. Journ. Geol. Soc. vol. xxi. p. 70 (1865). 



Geological Survey of Canada, Report, 1866, p. 230. Sterry Hunt/ in 

 the preface (p. 20) of the second edition, 1879 (the latest), of his Chemical 

 and Geological Essays, expresses himself thus : " The crystalline stratified 

 rocks were originally deposited as, for the most part, chemically formed 

 sediments or precipitates, in which the subsequent changes have been simply 

 molecular, or at most confined to reactions, in certain cases, between the 

 mingled elements of the sediments." 



l| See 'Proceedings of the Royal Irish Academy,' vol. x. p. 540. Sterry 

 Hunt has adduced in his favour the existence of Tertiary sepiolyte 

 in the Paris basin and at Vallecas near Madrid, " together with the 

 formation, at the present time, of a hydrous silicate of alumina and magnesia, 

 named neolite, a deposit from the waters in certain mines," and probably 

 resulting from the " decomposition of the magnesian minerals hornblende, 

 augite, and talc." But both cases may be safely set aside as totally inappo- 

 site. The sepiolyte, instead of being a "direct chemical precipitate, 1 ' 

 has been shown by Dr. Sullivan, President of Queen's College, Cork, and 

 Professor J. P. O'Reilly to be a secondary product, due to chemical alteration 

 of the original deposit ('Notes on Spanish Geology,' p. 171, 1863) ; and as 



