16 REVIEW—PRACTICAL GEOLOGY. 
Practical Geology. By W. Jnrome Harrison, F.G.S. London: W. 
Stewart and Co. Pp. 157, forty-two illustrations. Price 2s. 
Amone the many text-books of Geology it is a difficult, and in some cases a 
delicate task to recommend to the student which particular works to 
read. He cannot commence with too simple a work, one which interests 
the reader and conveys to him a general idea of the principles of geology; 
and once gaining the interest, he will be tempted to undertake the 
reading of some more advanced volume. There isa danger, however, to 
the student when pushing on his enquiries into the larger manuals, of 
becoming to some extent wearied with details, which observation will 
not enable him to enliven. Hence the great value of some practical 
experience in the field. Indeed, Mr. Harrison tells us how he attributes 
the success of his geological classes to a constant insistance on the 
necessity for field work, combined with the close examination, sketching, 
&c., of models and specimens; for an acquaintance with a few facts will 
enable the young student to appreciate the many. In the same way, 
even a hurried visit to a previously unseen tract of country will enable 
the more advanced student to read with interest and intelligence memoirs 
that previously seemed dry and uninviting. 
In the little work before us, Mr. Harrison has furnished the young 
student who is ready and anxious to go out in the field with a guide and 
companion, who tells him what and how to observe. Commencing with 
an account of the apparatus necessary, the author gives instructions how 
to set to work, and then takes his readers over all the British formations; 
pointing out their leading characters and fossils. So that the student 
who is possessed of a geological map, and will read the descriptions here 
furnished, with the map before him, and who will use every, opportunity 
of taking both into the field, may soon expect to become a good 
observer. 
The work is full of useful suggestions; and, besides the purely 
descriptive portions, Mr. Harrison takes care to combine many explana- 
tions of facts, as well as notes on the physical history of the deposits and on 
foreign strata. If some of the formations with which he is more 
intimately acquainted receive an apparently undue share of attention, as, 
for instance, the chapter on the Rhetic Beds, compared with that on the 
Silurian Rocks ; this is a very pardonable favouritism, rather than offence. 
The work has been most carefully prepared and edited, and contains 
references to all the more important researches made known up to the 
time of publication; and the way in which the subject is treated, giving 
evidence of much personal observation and thought, and of much 
heartiness and enthusiasm in the cause of geology, give us great pleasure 
in recommending it to all desirous of becoming practically acquainted 
with the geology of their country. 
H. B. Woopwarp. 
