THE MINERAL RESOURCES OF DEVON AND CORNWALL. 485 
some portions of the curve should be replaced by straight lines co- 
incident with the abscissa, answering to short intervals of silence, 
as in the case of the ordinary dog-whistle with a pea in it. Eapid 
changes of phase, as noticed by Helmholtz in his observations on the 
violin, the curve continually breaking off and recommencing in a 
different phase. The predominance, or the contrary of what may 
be termed the attendant noises, of every source of musical sound. 
The lecturer had intended to enforce the esthetical importance 
of his subject by a few musical illustrations upon instruments 
presenting marked differences of " timbre," but it was ruled by one 
of the secretaries that the admission of music would be derogatory 
to an institution whose avowed object is the cultivation of " Science, 
Literature, and the Fine Artsy 
THE MINERAL RESOURCES OF DEVON AND 
CORNWALL. 
Part II. 
ABSTEACT OF PAFER BY DR. R. OXLAND, F.E.S. 
(Read 17th February, 1876.) 
Close consideration of the subject is expedient, because, from the 
recently depressed conditions of the market for copper, tin, and 
iron, the opinion has been spreading that the days of success for 
mining in Devon and Cornwall have been numbered, and that 
these industries must die out and disappear Already very serious 
consequences have accrued, amongst which may be mentioned the 
abstraction of capital, and what is more important still, the re- 
moval of labour by emigration to other districts in Great Britain, 
but principally to the colonies and the United States. 
In the following remarks, the possibility of obviating these 
difficulties has been the principal object of consideration. 
The opening of a new railway, the South Western, which will 
shortly take place, will afford greatly increased facilities for the 
transport of supplies of materials, through districts hitherto unap- 
proachable for mining purposes, and for the conveyance of ores to 
shipping ports. It will also bring these districts into easy access 
for capitalists disposed to engage in the development of mining 
