40 
THE GEOLOGIST. 
di'ainagc of nine thousand one hundred and seventy three square miles, of whicli 
the Trent alone draws from fonr tlion.sand five iiundred square miles, the re- 
maining four thousand six hundred and seventy-three square miles supplying 
the Oiise, wo may form some idea where jiart of the " warp" comes from. 
What projiortioa river-sediincut from floods, ete., may supply, I eaunot pretend 
to say. Then we have the gradual wearing away of our Yorkshire coasts from 
two miles east of Bridlington Quay to Spurnt Point-, which is a distance of 
about forty-three miles. Along this coast we lose, on an average, six feet 
three inches annually. In fact new roads have continually to be made in con- 
sequence of the sea making such rapid encroachments on the land, wliich, when 
washed away, is taken up the Huuiber and constitutes another soiu'ce from 
which the " warp" is formed, and de])osited upon lands up the rivers, etc. 
1 think your correspondent, W. Nottingham, will be able to draw from 
these facts answers to both his questions. I believe that no otiier river, or 
rivers in England arc situated under such favourable circumstances for making 
the deposits called " warp" as arc the rivers above mentioned. — Dear sir, yours 
faithfully, EdWiUid Tindall. 
REVIEW. 
Mr. Tennanfs Mineraloyical and Geological Collections. 
We have received specimen cases of the two hundred, and three hundred 
selected examples of fossils and minerals, accompanied by the very useful cata- 
logue of ordinary British fossils, recently published by Mr. Temiant. These 
collections are designed as an initiary means of instruction for students and 
tyros. Notliing so much tends to facilitate and encourage the study of any 
science as a ready means of access to the principal objects referred to in the 
general descriptions and writings of authors. It is easy to accumulate speci- 
mens of rocks and fossils, and to form expensive collections ; but it is not so 
easy to form a limited and proper selection which shall at once illustrate the 
chief facts of a science, and be of real service to the student. 
Professor Tennant's well known intimate knowledge of minerals gives confi- 
dence to learners as to the correctness of the naming of the specimens, and his 
long experience in this class of rudimentary collections — first made by his im- 
mediate predecessor, Mr. Mawe, more than fifty years ago — shows itself in the 
completeness and perfection of the present cabinet coUeetions, in wliich, al- 
though the samples of fcssUs and minerals are of small size they are typically 
characteristic, and have every scientific advantage of displaying sufficiently 
their characters with that essential one of condensed space. The cabinets in 
which the collections are contained are strongly and neatly made, and, whether 
as useful and interesting presents at tliis season of gifts, or viewed in their 
proper light of aids to the compreiiension of elementary treatises on Geology 
or Mineralogy, they are well worthy of the reconnneudations given to them by 
Sir Charles Lyell, the late Dr. ManteU, and other eminent geologists, and in 
which we readily concur. 
