172 Reviews—Prof. Hull's Geological History. 
IV.—A SxkercH or GeronocicaL Hisrory, BEING THE NATURAL 
Hisrory oF THE Kartu anp or 11s Pre-Human Inuapirants. 
By Epwarp Huu, M.A., LL.D., F.R.S. 8vo. pp.179. Coloured 
Sections. (London, 1887.) 
| N order that our Science may draw recruits from all types of 
minds and from all quarters, and that it may exercise due 
influence on other classes of research, it is necessary that its soundest 
and most advanced conclusions should occasionally be put before the 
world in an interesting fashion, in brief and popular books. In the 
days of Sedgwick and Murchison the science was accounted a hard- 
walking, hard-working, fighting science, suited for healthy bodies, 
keen eyes, and deep-thinking minds, while Lyell and Darwin made 
plain that work could be done by all, whether they had the 
opportunity of world-girdling travel or could only watch worms in 
a back garden. We recovered from an era of species-making and 
minute subdivisions when (though others shared in the researches) 
Sir A. Ramsay and Professor Hull gave to the reading public a 
chance of seeing the result of this work in the successive geographical 
phases through which our own and other areas have passed. 
So when the latter author produces “A Sketch of Geological 
History,” part of a series of works on Universal History, evidently 
intended to be read by avery large section of the public, we have high 
expectations that even this most abstruse branch of the science will 
be dressed in its most attractive garb, that we shall find arguments 
(at least indicated) as well as facts, that all but necessary technicalities 
will be shelved, and that we shall be presented with a comprehensive 
view of the inorganic condition of the surface of our planet, and of 
the organic evolution which took place upon it. One in need of 
such things turns to the work and alights on this passage :—‘‘ The 
Lamellibranchs were also exceedingly abundant, yielding 1319 
species; the most abundant being the genera Avicula, Gervillia, 
Gryphea, Lima, Ostrea, Pecten, Pinna, Plicatula, Arca, Astarte, 
Cardium, Cypricardia, Gresslya, Leda, Modiola, Myacites, Mytilus, 
Opis, Pholadomya, Plewromya, and Trigonia; many of these genera 
survive in the seas of the present day.” Will he close the book in 
despair? Let us see. 
The work opens with a small division on the Consolidation and 
Cooling of the Globe, and the Plutonic Rocks. Perhaps this was 
inevitable, but surely the human mind would then hanker after 
some guiding principle to tell it how to digest the chaotic mass of 
“clay-slates, conglomerate, quartzite, and limestone,” which it is 
shortly called upon to consume, into some form of nourishing mental 
pabulum. It needs to be shown in what forms the rocks themselves 
contain the evidence on which the old physical geography may be 
restored, but that this evidence is sometimes unattainable because 
the strata may have been removed by denudation or be covered by 
subsequent deposits. In the first case some help may be obtained 
if the strata are conformable by the evidence given by previous and 
subsequent deposits; if unconformable, by the very nature of the 
movements which produce the unconformity. In the second case 
