Mr. Stevenson’s first communication on this subject was published in 1816, in vol. ii. of the Wernerian Transactions, in which he gives examples, from actual observation, of the wasting effects of the sea on various parts of the coasts of the British Isles. His second communication was made to the Wernerian Society in March 1820, and published in the _Edinburgh Philosophical Journal_ of that year.
In the fifth edition of Baron Cuvier’s “Essay on the Theory of the Earth,” reference is made to Mr. Stevenson’s theory. His papers are several times quoted in Lyell’s _Principles of Geology_, and the General Committee of the British Association at York in 1834 passed a resolution, “that Mr. Stevenson be requested to report to the next meeting upon the waste and extension of the land on the east coast of Britain, and upon the general question of the permanence of the level of the sea and land, and that individuals who may be able to supply information upon the subject be requested to correspond with him.”
Without discussing in how far Mr. Stevenson’s theory may be sound (for on such questions it is notorious that the views of geologists do not always coincide), it cannot be denied that his mode of dealing with the subject is original and interesting, and as the papers are not now accessible to the general reader, it may be excusable to give one of them _in extenso_. I also notice another feature which gives interest to the subject. In his illustrations he adopted a mode of representation which was peculiarly suitable for the object in view. It will be seen from Plate XII. that the sections are laid down on what is now known by engineers as _sectio planography_, which it is believed was used for the first time in illustrating this paper.
“ON THE BED OF THE GERMAN OCEAN, OR NORTH SEA. (Read before the Wernerian Natural History Society, 25th March 1820.)”
“The efforts of man in exploring the more occult processes of nature are necessarily much circumscribed, especially when his attempts are directed to the investigation of regions which his senses cannot penetrate. It has accordingly been with the utmost difficulty that his exertions have been rendered in any degree successful in prying into the bowels of the earth, or in his endeavours to ascend to the aërial regions. In proof of this, the limited excavations even of the most extensive mining works, have required the lapse of ages, and the powerful stimulus of commercial enterprise, for their accomplishment. From these the philosopher has not hitherto derived much light, to enable him to compare the theories which have been assigned by geologists to account for the various and discordant appearances of the structure of the globe. It has also been with much difficulty, and at no small personal hazard, that the philosophical inquirer has ventured to climb the highest mountains, to examine into the phenomena of the atmosphere. The balloon has indeed enabled us to attain still higher points of elevation; but as yet we do not seem to have made proportional progress in knowledge. In all such attempts to ascend the greatest heights or penetrate the deepest excavations, we still breathe in our own element, though under different modifications. If, however, we would explore the depths of the Ocean, we immediately encounter an element to which the organisation of our lungs is not at all adapted; the density of air, compared with water on a level with the surface of the sea, being in the ratio of one to about 850; and our difficulties must consequently increase in a very rapid proportion. Here therefore we are unavoidably left to conjecture on many points of our inquiries regarding this highly interesting subject. Even the ingenious contrivance of the diving bell contributes but little towards our investigations for ascertaining the nature of the bottom of the sea, at least to any considerable depth, on account of the difficulty of its application in situations exposed to stormy weather, and also of the increasing ratio of the pressure of the fluid as we descend. This curious machine, it is believed, was invented and employed, about the year 1720, by a Captain Rowe for raising the wreck of ships upon the coast of Scotland; and in the year 1778, the active mind of Smeaton first applied it to the operations of the engineer.