

Ancient Sea Margins. 323 



in the solution so that about half its bulk rises above the fluid, 

 the formation of ozone will immediately ensue, provided the 

 temperature be 15° to 20° R. Part of the ozone formed, acts 

 upon the saline solution and transforms part of its protoxyd of 

 manganese into permanganic acids, whose presence is indicated 

 by the beautiful deep red color which the solution assumes in 

 the course of a few hours. The same richly colored fluid is 

 obtained by shaking a solution of sulphate of manganese or 

 any other manganese salts in dilute phosphoric acid with ozon- 

 ized air. 



Having drawn up a detailed account of these and other exper- 

 iments, which before long will be published in " Poggendorff's 

 Annalen," I take the liberty to refer the readers of your period- 

 ical to that Journal. 



Enclosed you will find some specimens of manganese draw- 

 ings and writings produced in the manner above described. By 

 exposing them for a short time to the action of gaseous sulphurous 

 acid, you may easily destroy the image, &c, and restore them, by 

 ozonized air. 



Art. XXIV. — Ancient Sea Margins; by Robert Chambers. 



TO THE EDITORS OF THE AMERICAN JOURNAL OF SCIENCE AND ARTS. 



1 Donne Terrace, Edinburgh, July 9, 1847. 



Gentlemen : — I beg, through the medium of your pages, to 

 call the attention of American geologists to a line of investiga- 

 tion, from which I have been led by inquiries of my own in this 

 country, to expect some important results. It is that of natural 

 terraces, benches of land, and other forms of the surface, which 

 appear to indicate the former presence of the margin of the sea. 

 Hitherto ancient beaches have been chiefly inferred from the 

 presence of shells, but I am satisfied from my researches here, 

 that they can be detected with equal certainty from the configur- 

 ation of the ground and the presence of sand, gravel, and other 

 materials, such as are usually found on beaches. In Scotland, I 

 We by this means ascertained the existence of a series of ancient 

 Caches, from 64 to 616 feet above the level of the sea at high 

 w ater of ordinary tides, besides a few at inferior elevations, but too 

 m «ch huddled to be described with precision. And these are not 

 m arked at one place only, but many of them appear at various 

 P'aces all around the island. In each several place they are per- 

 fectly horizontal in the line of the ancient coast. In some places, 

 lw o, three, and four, may be distinctly traced on one hill-face to- 

 wards the sea, or in a valley which had formerly been the bed of 

 an estuary. Precisely the same group seldom appears in two 



