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A WANT expressed by many Geologists and A often felt by the Author, is a classified HANDY-BOOK OF ROCK NAMES. It is hoped that, until a better appears, this Manual may be useful to the Public.
To write such a work satisfactorily is no easy task. In other branches of Natural Science, such as Botany, Zoology, and the like, some systematic nomenclature has been followed, but in Geology no one system has been used, or all system has been ignored. It is not uncommon to find eminent Petrologists calling the same rock by several names, or, what is more perplexing, using for a rock a name already given to a totally different one. At the present time Rock names are in such confusion that if an observer names a rock, without at the same time mentioning his authority, he may be supposed to be referring to a rock, or even rocks, totally different to that which he intended to illustrate. This irregularity has caused many names to be used, not only unscientifically but also absurdly, as the original name may refer to a mineral or character not possessed by the rock or rocks to which it is now applied. From the above it is evident that a compiler of such a book as this Manual must run contrary to the opinions and
ists: therefore some is
T s could be well done.
In readers that this
T:: __ the field. Should 127.I.Tre of rocks, they must S E D Lirirks of the different 1.
3. 2 5 . necessarily, is far mi
n emay be of some small
this Manual, the We nos consists have been conseina
55 on general subjects from wher e be procured. Dana's sugu A
c te izmirition of Rock names have been in as fess practicable, while the oder names ir rocks are generally adopted, except when the are objectionable or better names hare since been proposed. Sach local names as were known are also given, as they may assist explorers in gleaning information about a country. To varioos felow-labourers I am much indebted: to D. Forbes, F.R.S., &c., for information; also to W. King, Dep. Sapt. Geol. Surv., India, and for his valuable assistance while arranging and classifying the rocks. I should also mention the names of the Rev. M. H. Close, M.R.I.A., &c.; Stackpoole Westropp, M.D., M.R.I.A., &c.; and H. Leonard, M.R.I.A. ; besides others who have supplied me with lists of local names.
Group N. Slate ... ... ... ... Page
Class 1. Subaqueous Rocks . ... ... ...
formed ... ... ... ... ...
Subgroup C. Fault-rock ... ...
cally, and partly organically formed ...
Subgroup C. Dolomyte ... ... ... .. 120
formed ... ... ... ... ... .
... ... 122