PROCEEDINGS—PERTHSHIRE SOCIETY OF NATURAL SCIENCE. Cxili 
stream, and to show how its carrying power depends on its velocity 
and its gradient; how its work is here destructive and there construc¬ 
tive; how its results vary according to the varying hardness and solu¬ 
bility of the rocks it encounters; and how the contour of its valley is 
largely determined by the nature of the climate. 
Nor must I linger over the last class of eroding agents to which I 
have referred, namely, the sea. I had intended, in illustration of this, 
to describe some of the effects of wave action which I have witnessed 
on the coasts of Cornwall and the Scilly Isles, where the full vio¬ 
lence of the Atlantic breakers is expended on the brittle granite crags. 
The effect, particularly in the Scilly Isles, is a succession of such 
fantastic shapes that the Scillonians point, with a certain display of 
pride, to a bewildering series of camel-rocks, elephant-rocks, etc., 
until one is tempted to ask, like the small boy in the menagerie, 
“which is which?” 
But I fear I have overtaxed your patience with a subject which to 
the uninitiated must appear somewhat dry. In excuse, I can only 
refer to what I said at the outset regarding the importance, to a 
student beginning the study of geology, of assimilating the idea of the 
universality of those processes of denudation. But even apart from 
an abstract study of Geology, everyone who loves his native country 
must experience some pleasure in being able to trace how her hills 
and valleys have come to assume their present forms. If we are able 
to do this, even to a very limited extent, then to the charm of lovely 
scenery and the interest of thrilling historic association will be added 
a third source of delight as we explore afresh the familiar fields of our 
native land. 
7th April, 1892. 
H. Coates, F.R.S.E., President, in the Chair. 
The following donations were intimated :— 
Museum—Perthshire Collection .—Nest of Water Ouzel, built on a 
tree—from Mr. C. L. Wood of Freeland. Pied Woodpecker, shot at 
Kilgraston—from Mr. H. Young. 
Library .—Books from Mr. A. Coates and Dr. H. R. Mill. 
The Marquis and Marchioness of Breadalbane; Mrs. A. E. 
Pullar, Durn; Miss Wallace, Knowehead; Mr. H. Robb, Balhousie 
School; Sheriff Jameson; Dr. A. Campbell; Mr. J. M‘Ewan; Mr. 
J. Chalmers; Rev. T. Crawford, B.D.; Mr. J. Hay; Sir J. Kinloch, 
Bart., M.P. ; Mr. J. Mackay, New Scone; Mr. G. Miller; Mr. J. 
Leslie; Mr. R. Brand; and Mr. T. West Carnie, London, were 
elected Ordinary Members, and Mr. H. R. Mill, D.Sc., F.R.S.E., 
a Corresponding Member. 
