148 Chronicles of Science. [ Jan. 
A far more extensive inquiry has been made by Mr. Wallace of 
Alston Moor, with a view to the solution of this problem, and he is 
fully persuaded that, as far as this district is concerned, he has arrived 
at the true solution.* The balance of evidence is greatly in favour of 
the hypothesis put forth. It is not possible, within the limits of a 
summary notice, to explain satisfactorily the views of this writer. 
Suflice it to say, that Mr. Wallace regards the mineral lodes as chan- 
nels through which, the waters accumulated on the surface, and 
percolating the rock, were discharged. These waters are supposed to 
derive from the adjacent rocks, or from some other source, the minerals 
which are subsequently deposited in those larger channels. 'The rich- 
ness of any lode is determined by several conditions, all of which, 
however, may be regarded as disturbing causes. For example if, into 
a main channel of fissure, several lateral fissures flow, it is found that 
along the main fissure or lode, it is productive of metallic ores at 
these parts. 
Several good examples of this are given in Mr. Wallace’s beautifully 
executed map; one of these we copy. It is a portion of the great 
Rodderup Fell vein, and shows that the lode is unproductive except 
where the numerous small lateral veins, as shown in our drawing, 
have been channels in which fluids have been collected and conveyed 
to the larger fissure. The vein has proved remarkably productive of 
S 
lead in those parts. Mr. Wallace’s book is a valuable contribution 
to the very limited literature which exists in the English language, on 
mines and mineral deposits. That attention has been awakened to 
this question, is further proved from the fact, that at the last meeting 
of the Miners’ Association of Cornwall, two Cornish miners contributed 
papers on the subject. 
Such are the matters of interest connected with British Mining, 
which have recently presented themselves. 
As illustrating the value of our mines in relation to those of other 
countries, it is satisfactory to be able to examine two very recently 
* «The Laws which reeulate the Deposition of Lead Ore in Veins : Illustrated 
by an Examination of the Geological Structure of the Mining Districts of Alston 
Moor.’ By William Wallace, Edward Stanford, London. 
