You are aware that one of the most interesting geological problems of our day is, that of the rise and fall of the land in Sweden: a good deal has been said on both sides. The Academy of Sciences at Stockholm has, however, taken measures to settle the question. It has chosen sixteen stations, chiefly between Haparanda and Strömstad, where daily observations are made and recorded on the height of the sea. This is the great point to be determined; hitherto, it has been left too much to chance, or to the attention of casual travellers. In connection with it, the rate of elevation would be ascertained, whether it is everywhere the same, and continuous or intermittent. It has been stated, that at Stockholm the rise was four feet in 100 years, and greater still in the Gulf of Bothnia; but Mr Erdmann of Stockholm, in a memoir on the subject, shews reason to doubt the fact. The house in which he resides, standing near the port, was built at the beginning of the seventeenth century; when the water of the adjacent sea is raised two feet above the ordinary level, which happens but rarely, his cellar is always flooded. Therefore, assuming the rise of the land at four feet in the century, it follows, with only half that height, that when the house was built, the floor of the cellar was constantly under water, which is hardly likely to have been the case. He mentions also the observations made at the sluices of the Mælar Lake, from which a rise of one foot in a century had been inferred, but states that a defect in the measuring-scale completely invalidates the results. In addition to what the Academy are doing, he has had a reference-mark cut on the face of the steep rock of the citadel, so that, in the course of a few years, we shall be in a position to judge in how far the theory of elevation and subsidence of land in Sweden is borne out by the facts.
This reminds one that coral-reefs have been much talked about of late: the opinion is, that they grow in height about an inch and a quarter yearly. Means have also been taken to decide this question. When the American Exploring Expedition lay at Tahiti, Captain Wilkes had a stone-slab fixed on Point Venus, and the distance from it to the Dolphin Shoal below carefully ascertained, so that future measurements will test the theory.
Mr Wells, of Cambridge, Massachusetts, shews that there are causes, besides those usually assigned, which will produce stratification, or those interruptions which occur in deposits. He was engaged in examination of soils; and washed earth through a filter, at times so slowly as to occupy fourteen days in the process, and dried the sediment at a temperature of 250 degrees. This, when dry, he found to be perfectly stratified in divisional planes; sometimes accordant, at others irregular, and shewing difference of materialnamely, silica and alumina:
'The strata so produced,' he says, 'were in some instances exceedingly perfect and beautiful, not altogether horizontal, but slightly curved, and in some degree conforming to the shape of the funnel. The production of laminæ was also noticed, especially by the cleavage of the strata produced into thin, delicate, parallel plates, when moistened with water. These arrangements, it is evident, were not caused by any interruption or renewal of the matter deposited, or by any change in the quality of the particles deposited, but from two other causes entirely distinct, and which I conceive to be thesefirst, from a tendency in earthy matter, subjected to the filtering, soaking, and washing of water for a considerable period, to arrange itself according to its degree of fineness, or, perhaps, according to
the specific gravity of the particles, and thus form strata; and, secondly, from a tendency in earthy matter, consolidated both by water and subsequent exsiccation, to divide, independently of the fineness or quality of its component particles, into strata or laminæ.'
Whether Mr Wells be right in his conclusions, remains to be proved; geologists will not fail to examine into his proofs. They may, however, remember, that Agassiz has remarked, that saw-dust through which water has been filtered, will 'assume a regular stratified appearance;' and that, in beds of clay and clay-slate, the deposits are such as to justify these conclusions.
The Felix Meritis Society at Amsterdam propose to give their gold medal, or twenty gold ducats (L.10), for the best answer to the questions'What are the re-agents the most proper to demonstrate, in a sure and easy way, the presence of ozone, and to determine its quantity? Does ozone always exist in the atmosphere, and under what circumstances, regard being had to the seasons and hour of the day, is it found to increase or diminish? From what properties can it be inferred that ozone is favourable or hurtful to the animal economy, and what has experiment made known in this respect, particularly in the appearance or disappearance of epidemic diseases?'
The treatises are to be distinguished by a device, not by the author's signature: they may be written in English, French, Dutch, or German, and are to be sent addressedFelix Meritis , Amsterdam, before May 1, 1853. The Society reserve to themselves the right of publishing the successful paper at their own cost.