I know no more interesting problem in geology than the question, What was the great agency which brought the surface of northern Europe into the condition in which it is now occupied by man? and it seems marvellous that geologists should not yet be agreed as to what that agency was.

Our own country of Scotland is strewed with boulders, many of immense size, and which we allow have been somehow transported to their present sites from remote regions. Rocks on our hill-sides have been ground down, smoothed, and striated by ponderous bodies which have come against and rubbed upon them.

This paper deals with various formulæ of definite integration which are, in general, put into forms in which they enable us with great ease to sum a number of infinite series. As a simple example of such a formula the following may be given:—

From this it is easy to deduce innumerable results, of which the annexed are some of the more immediate.

The Council having awarded the Makdougall-Brisbane Prize, for the biennial period 1876–78, to Professor Geikie, for his Memoir “On the Old Red Sandstone of Western Europe” published in the Society's Transactions 1877–78, which forms one of an important series of contributions by Professor Geikie to the advancement of geological science, the Medal was presented to him by the Chairman, with the following remarks:—

IN accordance with what he was told was the practice on such occasions, he would shortly explain, first, the purpose for which this particular prize was instituted, and, second, the nature of the memoir and work by Professor Geikie for which the prize had been awarded to him.

This solar spectrum contains measures of about 2000 fixed lines, or fully a third more than are represented in Ångström's worthily celebrated Normal Solar Spectrum Map, which is taken as the standard reference for “place.” The observations were made in Lisbon during the summers of 1877–8, with apparatus prepared by the author; who aimed at including everything visible, from the extreme red to the extreme violet ends of the spectrum, so far as that is amenable to the human eye after transmission through glass.

On a former occasion I drew attention to methyl sulphate of ammonium as a suitable material for the preparation of methylamine by heating it with quicklime. There is another and better method of arriving at the same result, the extreme simplicity of which was probably the cause of its being overlooked at the time.

The following brief statement concerning “Reh” is chiefly derived from the Report of the Committee on Reh, November 1878:—

Large tracts of country in the north-west of India have from time immemorial been covered with a white alkaline efflorescence, which renders them incapable of supporting any form of vegetable life. These tracts are called “usar” plains, and the white efflorescence “reh.”† The appearance of this reh on the surface is owing to the subsoil water, which is impregnated with sodium salts, being sucked up to the surface by capillary attraction and there evaporated by the fierce heat of the Indian summer sun. The reh is often very irregularly distributed,—bald patches occurring in the midst of cultivation, or cultivated patches surrounded by reh,—and this capricious distribution has rendered a right comprehension of its mode of production difficult.

This paper is a continuation and a fuller explanation of the previous one, in which it was attempted to show why barometric depressions, or storms, move forward. In our present state of knowledge, exceptional cases in such an investigation are always to be found, and the subject is consequently taken up in a general point of view. It is attempted here to be shown, not how depressions always move, but how, under certain well-known circumstances, they may move.

I cannot, of course, commence the discharge of the duties of President of this learned and celebrated Society, without expressing my profound gratitude to the members for their unexpected kindness in elevating me to this chair, and my intense appreciation of the distinction they have thereby conferred upon me. It is a position of which any man, however high his reputation or however great his attainments, could not fail to be proud. To me your favour has laid me under the greater obligation, that I am painfully conscious that I am entirely without pretensions to the special qualities which have generally determined your choice.