Note 220 — Chapter XXXVI · THE PLATEAUX

In the course of my investigations I have had many hundreds of thin slices cut from the Tertiary volcanic rocks for microscopic determination. These I have myself studied in so far as their microscopic structure appeared likely to aid in the investigation of those larger questions of geological structure in which I was more especially interested. But for further and more detailed study I placed them with Dr. Hatch, who submitted to me the results of his preliminary examination, and where these offered points of geological import I availed myself of them in the memoir published in 1888 in the Transactions of the Royal Society of Edinburgh. I have retained most of these citations in their place in the present volume, and have supplemented them by notes supplied to me from fresh observations by Mr. Watts and Mr. Harker. Professor Judd, in a series of valuable papers, has discussed the general petrography of the Tertiary volcanic rocks (Quart. Jour. Geog. Soc. vols. xxxix. xli. xlii. xlvi. xlix.)