I Used to think that the corrugations of the earth's crust were due to compression through the shrinking of the interior. To judge of the sufficiency of this cause the first thing to be done is to seek a measure of the compression, and then to compare the result of the effects of cooling with the actual amount of compression. The most satisfactory measure appears to be the thickness of the layer which the corrugations would form if levelled down. The question then becomes one of how much. In 1863 Lord Kelvin (then Sir W. Thomson) formulated a law of secular cooling upon the hypothesis that the interior is solid. Adopting a probable value for the contraction of rocks in cooling, I calculated the thickness of the layer which would be produced by the corrugations resulting, and found it far short of that which the existing inequalities would form if levelled down. Mr. Mellard Reade and Dr. Davison subsequently discovered the existence of a level of no strain within the crust, and this greatly reduces the possible amount of corrugations. The conclusion at which I arrived was that, on the hypothesis of a solid globe, secular contraction through cooling would not account for the corrugations.

The name ‘Balangoda group’ is proposed for a series of granitic and pegmatite-like rocks, intrusive in, but distinct from, the Charnockite series; first met with in the Balangoda district, but evidently widely distributed over a large area between Balangoda and Hatton. The rocks are best described as granites, but occur most often in rather narrow dykes, after the manner of pegmatites. Yet there is no reason for separating the smaller from the larger masses, and the term granite is applied to both. The group (of which a more detailed account will ultimately be needed) includes in particular zircon granite, allanite granite, magnetite granite, and granite without conspicuous accessory minerals; as well as the probably similar rocks in which the hitherto unlocated minerals geikielite, baddeleyite, rutile, fergusonite, thorite, thorianite, etc., may be looked for; and the vein of pegmatite at Gampola, which consisted of quartz, felspars, and biotite, with apatite, ilmenite, tourmaline, and the new mineral described as thorianite as accessory minerals.

These granites are intrusive in the Charnockite series, and though frequently occurring in lenticular masses (Denagama) with a disposition parallel to that of the foliation planes of the charnockites, have often been observed to transgress these foliation planes and to behave as intrusive rocks. Contact phenomena have not, however, been observed, except perhaps in a slight tendency to a peripheral fineness of grain in the intrusive rocks. At the junctions granite and charnockite are usually welded together, there being no absolutely hard line of separation, although the junction may be called sharp; in the case of the larger masses no good junctions have been seen.

Four articles in the Biarritz Association Bulletin, and a series in the last publications of the Soc. Géol. de Fiance, discuss the problem of Pyrenean ophite by conjectures regarding the obscure points of greenstone in the shifting sands of the Biarritz coast. When first seeking new facts at Biarritz, I discovered the red marls and gypsum that accompany the ophite to be recurrent in the undisputed Upper Cretaceous of Croix d'Ahetze, and I followed the Biarritz rocks to Zumaya and Loyola in the attempt to trace their relations. Having subsequently proved that the other red clays mapped as Trias are brick clay of post-Glacial origin, contemporary with a tooth of Elephas primigenius and anterior to flint implements described as Pliocene, and having vainly demonstrated the continuity of the rocks of the Spanish coast by both maps and fossils, I would invite geologists to profit by the light railways and other advantages which to-day enable the fundamental section of Pyrenean geology to be easily studied in its unmistakable continuation.

There is no essential difference between Nos. 1, 2, and 3, and No. 4: only differs in being harder, not liable to disintegration by water, and in containing more arenaceous and less argillaceous matter than the other samples. Calcareous matter in all the samples is from 15 to 20 per cent., and consists almost entirely of shells of Foraminifera. There is a considerable amount of sulphur, chiefly as pyrites, greatest perhaps in No. 3, and fragments of Manjak occur in No. 1.

In criticising my paper Professor Hull “regrets very much to have found it necessary to make these remarks.” I regret it too, because he only raises issues whioh have been discussed, and, I hoped, settled years ago. But I fear that Professor Hull has not given attention to modern Jurassic literature. He says that Midford Sands is “a name unknown to geologists in general.” Whereas, as the Editor points out, Professor Phillips was the author who amused himself with inventing this fanciful name, to adopt my critic's language. And in the 1879 edition of Sheet 44, at the foot of which appears the name E. Hull, there is on the margin this legend, “G 4, Midford Sand.”

The author refers to his work in former years among the High-level Plateau Gravels south of the Thames, chiefly in Berks and Surrey, the results of which were given in various papers from ten to twenty years ago.6 The present note may serve as a supplement to those papers, in which the conclusion was arrived at that the gravels in question were to be regarded as distinctly of riverine origin and, upon the whole, of Pliocene age.

In 1844, in his “Synopsis of the Carboniferous Fossils of Ireland,” F. M'Coy described and figured the species Goniatites fasciculatus (p. 13, pl. ii, fig. 8), a Goniatite referable to the genus Pericyclus, Mojsisovics. The type-specimen is preserved in the “Griffith Collection” in the Museum of Science and Art, Dublin, and has been re-figured (as Pericyclus fasciculatus) by Dr. A. H. Foord in his “Monograph on the Carboniferous Cephalopoda of Ireland” (pt. iv, 1901, pl. xxxvii, figs. 5a, b); where its locality is given as Millicent, Clane, county of Kildare.