AIM OF THE PRESENT PUBLICATION. xxvii of the impersonal character of the authorship. It is, I am aware, very imperfect and indeed unfinished, for the limits to which I was confined obliged me to bring it to an abrupt close. As, however, it contains general information which may be acceptable to some readers (and in this respect might be read first by those to whom the subject is not already familiar), I have thought it best to retain it here. The Appendix contains a few documents by different writers, referred to in the volume; and a good Index has been added, by the aid of which I trust that it will be easy to ascertain the progress of my observations or opinions on any part of the subject. I The whole of my minor writings on glaciers are not included in this volume. I shall close this introduction with what is, believe, a correct list of. those which are not reprinted. The reason of their omission has been, for the most part, my reluctance to recal the memory of controversies long since concluded. My desire is, that this volume may contain as few traces as possible of personal discussions, nor one sentence which might occasion pain to any reader. The main intention, indeed, of the present publication is to appeal directly to what I have written as evidence of my share in establishing a just theory of a great natural phenomenon,—that of glaciers; and to do this by rendering accessible to all readers the documents by means of which my claims to originality must be decided. It is not for me to add to or take from the text of what I have written. It is also more becoming that others, rather than myself, should be its interpreters, and the judges of what, after a fair and impartial study of the whole, my writings shall be held to establish. This is the only favour that I ask. COLLEGE OF Edinburgh, February 1859. PAPERS ON GLACIERS NOT INCLUDED IN THIS VOLUME. 1842. The Glacier Theory. Edinburgh Review for April 1842. [I at first intended to reprint this article in the present volume. But I found that it would ill accord with the character of the other contents. Being based, so far as the physics of glaciers are concerned, on the rude and imperfect data which alone existed in 1841 when it was written, its speculations and its questionings are already in a great measure obsolete, and would have served no other purpose but to show the great advance which the subject has since made. The longest part of the article was upon the geological aspect of glaciers, one hardly touched upon from the succeeding papers of the volume. gether it seemed to me that, though historically not without interest, yet its insertion would distract the attention of the reader from the main purposes of this publication. Some of the more popular and descriptive parts of the article were reprinted as an introduction to the abridged edition of my Travels.* The paper in the Edinburgh Review was translated into French, and printed entire in the Annales de Chimie, under the direction of M. Arago.] Alto 1843. Historical Remarks on the Discovery of the true Structure of Glacier Ice. Edin. New Phil. Journal, Jan. 1843. . 1843. Three papers on Glaciers. Proceedings of the Royal Society of Edinburgh. Read 6th and 27th February, and 20th March 1843. [These papers contain the substance of some of the chapters of the Travels in the Alps, then in preparation. The third contains the first description of the plastic models, with illustrative *Tour of Mont Blanc and of Monte Rosa. A. and C. Black. 12mo. 1855. PAPERS NOT INCLUDED IN THIS VOLUME. xxix figures. The Keith Prize was awarded to the author for these communications.] 1845. Reply to Mr. Hopkins on the Motion of Glaciers, with reasons for avoiding further controversy. Phil. Magazine, May 1845. 1845. Tenth Letter on Glaciers. London and Edin. Edin. New Philos. Journal, See page 169 of January 1846. [Chiefly controversial. this volume.] 1846. The Article on Glaciers in Johnston's Physical Atlas. [Principally geographical and topographical.] 1855. Remarks on the Rev. H. Moseley's Theory of the Descent of Glaciers. Proceedings of the Royal Society of London, 14th June 1855. 1859. Remarks on a paper "On Ice and Glaciers," in the last number of the Philosophical Magazine, in a letter to Professor Tyndall. [Will probably appear in the Phil. Magazine for March 1859.] The first edition of Travels in the Alps of Savoy, &c., was published in July 1843; the second edition in June 1845. The work entitled Norway and its Glaciers, etc., was published towards the end of 1853. PAPERS ON THE THEORY OF GLACIERS. I. ON A REMARKABLE STRUCTURE OBSERVED BY THE AUTHOR IN THE ICE OF GLACIERS. (Read to the Royal Society, Edinburgh, Dec. 6, 1841).* Obscurity of the Theory of Glacier Formation-Ribboned Structure described-Its Course traced on the Glaciers of the Aar and Rhone-Probably perpendicular to Lines of greatest Pressure-Also perpendicular to Fissures or Crevasses— Analogy to Slaty Cleavage in Rocks-Physical Cause of both perhaps similar. † THE object of the present short communication is little more than to announce and describe a peculiarity which the Ice of Glaciers frequently exhibits, interesting in itself as connected with the theory of their formation and propagation, and perhaps having a bearing upon the explanation of some facts long felt by geologists to be perplexing. Had I yielded to my own first impulse, this communication would have formed but a part of a much more extensive one, intended to give such an account, as I best might, of the present views entertained respecting the mechanism and conservation of glaciers, and the curious and interesting question of their ancient extension, and perhaps vast geological influence in producing some of the latest evidences of revolution on the surface of the globe. When I considered, however, the great * Edinburgh New Philosophical Journal for January 1842. B |