David Forbes

I.—On the Alleged Hydrothermal Origin of Certain Granites and Metamorphic Rocks

The study of the crystalline and metamorphic rocks seems hitherto to have been rather avoided by British geologists, who have more exclusively devoted their attention to the stratified and fossiliferous deposits, and left this field of research all but entirely to be cultivated by their continental brethren.

VI.—On Meteorites2

On the previous occasions upon which I have had the honour of lecturing in this hall, my observations were confined to the consideration of the structure of the earth beneath our feet. Now, however, I would crave your indulgence still further, when I attempt to carry your thoughts with me to infinitely higher regions by directing your attention to the study of what may be termed the mineralogy of the heavens above us.

I.—On the Contraction of Igneous Rocks in Cooling

Upon commencing, in 1847, the special study of the igneous rocks, I, no doubt in common with many others, took for granted the conclusions arrived at experimentally by Professor Bischof, of Bonn, as to the amount of contraction which such rocks would undergo when passing from the state of hot liquidity to that of cold solidity; and I did so, not after any critical examination of the details of Bischofs inquiry itself (the most important of which are contained in a memoir published in Leonhard und Bronns Jahrbuchfor 1841), but merely in deference to authority, since these conclusions had apparently received unquestioned acceptation from geologists in general.

I.—On Dr. Sterry Hunt's Geological Chemistry

In considering the mutual relations of the sciences of Geology and Chemistry, the student must always bear in mind which of these two sciences is to form the basis or starting point for his inquiry, for this cannot fail to exercise an important influence on his reasonings and deductions.