ment of the subject goes into more local detail than Prof. Hull, his work in 
this respect exhibiting some resemblance to the second of those cited above, 
and by this means he succeeds in producing a very vivid picture of the 
geological structure of Ireland. In some points of stratigraphical geology 
he differs in opinion from the survey of which he is a member — the Lower 
Silurian rocks of the survey are for him Cambro-Silurians — the Old Red 
Sandstone of Ireland, at any rate, follows the Yellow Sandstone into 
the Carboniferous series ; and his treatment of the unmistakable members of 
the latter differs somewhat from that which must be regarded as orthodox 
from a survey point of view. The author does not, any more than Prof. 
Hull, recognise the presence of Pre-Cambrian rocks in Ireland, so that we 
must wait until Mr. Hicks can make an exploration of the Sister Isle, 
before we can hope to hear of the existence of Irish Pebidians, Dimetians, 
and Arvonians. 
In his first section Mr. Kinahan treats of the Sedimentary formations ; 
his second is devoted to the metamorphic and eruptive rocks, upon the 
nature and production of which, as is pretty well known, he holds certain 
opinions of his own. His views with regard to metamorphism are stated 
as follows : “Metamorphic and eruptive rocks. . . are intimately connected, all 
being indirectly due to Metamorphic Action. . . . One kind of metamor- 
phism is Regional , or extends over large areas. The rocks affected by it 
seem to have been under the influence of intensely heated water or steam 
which, as it were, stewed them, from which the action may be called 
Metapepsis. Another kind is merely Local , its effects being only found 
immediately adjoining intruded masses of rocks, or in the vicinity of 
vents where gases, steam, or other products of vulcanicity found egress. 
When typical, this kind of metamorphism producs in the rocks an appear- 
ance as if they were baked, from which it may be called Paroptesis. It 
is not, however, always typical, as many of the altered rocks must 
have contained moisture, which, when heated into steam, would give 
results more or less similar to Metapepsis, except that the action would 
be confined to limited areas. . . . There is a third class of Metamorphism 
which is also local. It is due to the introduction and action of chemical 
substances from without ; it has been called Methylosis. . . . Metapep- 
tic action is the metamorphism that is most interesting to the geologist, as 
it is by the extreme action of it that eruptive rocks have been formed.” 
From this point of view Mr. Kinahan forms a classification of the Eruptive 
and Metamorphic rocks, in accordance with which he treats those which 
occur in Ireland in the same local detail as the sedimentary deposits. 
A third section treats of the superficial accumulations and includes not 
only a discussion of the Drift and Glaciation of Ireland (the details of the 
latter do not appear to be quite so well settled in Mr. Kinalian's mind as in 
those of some other observers), but also an account of ancient sea-margins, 
great deposits, and the pre-historic remains of man, upon which Mr. Kinahan 
has naturally a good deal to say. We have here also a chapter on the 
Post-Pliocene Mammalia. 
Section IV. treats of the physical features of the country ; and Section V . 
of its economical products in the shape of minerals, building and other stones , 
and mineral manures. This last section is of much practical importance, and its 
NEW SERIES, YOL. III. — NO. IX. F 
