I have already mentioned, that I had long observed great masses of _debris_, or an extremely coarse species of pudding-stone, situated on the south as well as north sides of those schistus mountains, where the alpine strata terminate in our view, and where I had been looking for the connection of those with the softer strata of the low country. It has surely been such appearances as these which have often led naturalists to see the formation of secondary and tertiary strata formed by the simple congestion of _debris_ from the mountains, and to suppose those masses consolidated by the operation of that very element by which they had been torn off from one place and deposited in another. I never before had data from whence to reason with regard to the natural history of those masses of gravel and sand which always appeared to me in an irregular shape, and not attended with such circumstances as might give light into their natural history; but now I have found what I think sufficient to explain those obscure appearances, and which at the same time will in some respect illustrate or confirm the conjecture which has now been formed with regard to the operations of the globe in those regions. In describing the vertical and horizontal strata of the Jed, no mention has been made of a certain pudding-stone, which is interposed between the two, lying immediately upon the one and under the other. This puddingstone corresponds entirely to that which I had found along the skirt of the schistus mountains upon the south side, in different places, almost from one end to the other. It is a confused mass of stones, gravel, and sand, with red marly earth; these are consolidated or cemented in a considerable degree, and thus form a stratum extremely unlike any thing which is to be found either above or below. When we examine the stones and gravel of which it is composed, these appear to have belonged to the vertical strata or schistus mountains. They are in general the hard and solid parts of those indurated strata, worn and rounded by attrition; particularly sand or marl-stone consolidated and veined with quartz, and many fragments of quartz, all rounded by attrition. In this pudding-stone of the Jed, I find also rounded lumps of porphyry, but have not perceived any of granite.[32] This however is not the case in the pudding-stone of the schistus mountains, for, where there is granite in the neighbourhood, there is also granite in the pudding-stone. [Note 32: A view of this object is seen in plate 3d. It is from a drawing taken by Mr Clerk of Eldin.]