116 
REVIEWS. 
The Ground beneath us, its Geological Phases and Changes : being 
Three Lectures on the Geology of Clapham, &c. &c. By Joseph Prest- 
wich, E. B. S., &e. London: Yan Yoorst. 1857. 
A Geological Enquiry respecting the YJater-bearing Strata of the 
Country around London, &c. &c. By Joseph Prestwich, E. R. S., 
&c. London: Yan Yoorst. 1851. 
The unpretending and well-written essay on the geology of the district 
around London, which we have placed at the head of this article, would 
of itself be sufficient to justify the position that Mr. Prestwich deservedly 
holds among English geologists. Although it only professes to treat of 
the geology of the neighbourhood of Clapham, yet, from the similarity 
of the geological phenomena around London, it is equally applicable to 
many districts in the vicinity of the metropolis. As Mr. Prestwich him¬ 
self says, in his Preface:— 
“ The subject is one of more than local interest, for Clapham stands upon ground 
which forms part of the London Tertiary district, and consequently the account here given 
of the Drift and of the Tertiary strata is equally applicable to the ground beneath London 
and to some distance around; and no separate work having yet been published of the 
Geology of London and its neighbourhood, and this account, though general, touching 
upon most of the leading points, besides including a short discussion of some views not 
yet brought forward elsewhere, especially those respecting the Drift, I trust that this 
sketch may also be of some use as a guide to those even who have made Geology more 
particularly their study, and that it may supply for the present the want of a more spe¬ 
cial treatise.” 
In the first of the three Lectures Mr. Prestwich discusses the drift 
gravel of Middlesex, and gives some very interesting facts respecting its 
physical character and distribution. It forms, as is well known, the 
matrix of all the surface pumps and wells of London, and gives a supply 
of water, which, though now somewhat impure, is, on the whole, of 
great value to many portions of the metropolis. We ourselves know of 
some pure wells of spring water in dark cellars of murky houses in back 
streets, which, to one not so fastidious as a teetotaller, would seem sweet 
and fresh; but, in most places, where this water is either pumped or 
comes to the surface, it is contaminated by the sewage of the over- 
populated streets. 
We cannot do more than advert to the very interesting discussion as 
to the origin of the subangular and rounded chalk flints, and other rarer 
pebbles found in the London Drift, and pass on to the organic remains 
which have been found in it:— 
“ Amongst the Quadrupeds whose remains have been recognised, we have an Ele¬ 
phant, a two-horned Rhinoceros, a large animal of the feline tribe related either to the 
Lion or the Tiger, a large Hippopotamus, a great Bear, a formidable Hyaena, the Red- 
deer, the Rein-deer, the Wolf, an Ox, and a Horse. This must strike you as a very sin¬ 
gular group ; for, associated with a few animals still common in these latitudes, we here 
have, on one side, animals of a class now living only in the hot and torrid zones, and, 
on the other, animals now confined to the cold and frigid zones. To determine their 
relations and to draw correct inferences with respect to the climatal conditions prevailing 
during the period at which they lived, are questions requiring extreme caution.” 
