August 20, 1886.] 



SCIENCE. 



163 



by a simultaneous gliding of its whole mass, as be- 

 lieved by de Saussure. All these laws, deduced from 

 a first, but attentive, study of the phenomena of the 

 glaciers, were, at that time, — excepting that of the 

 moraines, — new for science. They were expounded 

 by me, and illustrated by diagrams, at the meeting 

 ■of the geological society of France, in session atPor- 

 rentruy, the same summer of 1838 ; and I had the 

 great satisfaction of seeing them fully confirmed by 

 the subsequent observations of Agassiz and others, 

 which furnished the precise numerical data then 

 wanting for their complete elucidation. This paper, 

 liowever, though duly mentioned in the proceedings 

 ■of the geological society {Bulletin, vol. ix. p. 407), 

 was not printed, owing to a protracted illness of its 

 author in the winter following But on the occasion 

 of a claim by Prof. J. D. Forbes to the discovery of 

 the laminated, or ribboned, structure of the ice, the 

 portion relative to this subject was printed, and the 

 whole manuscript, on a motion of Agassiz, was de- 

 posited, by a formal vote, as a voucher, in the 

 archives of the Society of natural sciences of Neu- 

 chatel, the original draft being now in my hands. If 

 I mention this circumstance, it is because the regret- 

 table omission of the publication of my paper was the 

 occasion of the unfortunate misunder.*tanding which 

 estranged two such men as Agassiz and Forbes, and 

 which I feel bound, in a measure, to explain." 



The manuscript referred to in the latter part of 

 this citation was sent to the Society of natural 

 sciences of Neuchatel early in 1883, was read at the 

 session of the society on the 13th of April, 1888, and 

 published in its Bulletin of the same year. I have 

 a copy of the published paper, which I received from 

 the secretary of the Neuchatel society. It is in 

 French, as first written, and its title page, and also 

 the cover, bears the heading, ' Observations sur les 

 glaciers des Alpes en 1838, par M. Arnold Guyot.' 

 I had thus, in Guyot's memoir of Agassiz, and this 

 publication by the Society of natural sciences of Neu- 

 chatel, the fullest authority for my statements, and 

 also, in this and other ways, abundant reason for 

 confidence in Professor Guyot. Moreover, his 

 memoir of Agassiz bears evidence throughout that 

 his friendship for Agassiz, as I know from long and 

 intimate intercourse with him, was, to the end, that 

 of a brother. 



In the same memoir, Guyot says of Venetz and 

 Charpentier — names mentioned by Mr. Marcou — 

 and of Agassiz''s great results : 



"If to Venetz and Charpentier belongs the honor 

 of having first proved the transportation of the Swiss 

 erratic bowlders by the agency of ice, and the exist- 

 ence of great glaciers formerly extending to the Jura, 

 to Agassiz we must accord the merit of having given 

 to these facts their full significance ; of having 

 brought them before the world at large, and having 

 made the glacial question, as it were, the order of the 

 day. By his sagacity he found glacial action where 

 it was never suspected before, pointed it out to the 

 astonished and unbelieving English geologists on their 

 own soil ; found it in North America ; traced it with 

 undoubted evidence in the temperate regions of 

 South America ; and believed, though with hardly 

 sufficient reason, that he had seen it on the vast 

 plains of the Amazon. He proved the phenomena to 

 be well-nigh universal." Thus Guyot does justice to 

 his friend, and recognizes the earlier work of Venetz 

 and Charpentier. 



My academic memoir of Guyot closes with the fol- 



lowing sentence: "As fellow-students, we have 

 special reason to admire in Guyot — as he wrote of 

 Humboldt — ' that ardent, devoted, disinterested love 

 of nature, which seemed, like a breath of life, to per- 

 vade all his acts ; that deep feeling of reverence for 

 truth, so manifest in him, which leaves no room for 

 selfish motives in the pursuit of knowledge, and finds 

 its highest reward in the possession of truth itself.' " 

 I know this to be a just tribute. 



Mr. Marcou's remark condemnatory of Professor 

 Agassiz's 'successor at Harvard college,' for "hav- 

 ing denied, in toto, in a publication founded by Agas- 

 siz, — ' The memoirs of the Museum of comparative 

 zoology,' — his [Agassiz's] great discovery of the 'ice 

 age,' but having, more than that, ignored him alto- 

 gether as the discoverer of the existence of ancient 

 glaciers in the British Dominions, in New England 

 and New York, in Brazil, in the Straits of Magellan, 

 and in Chili," is essentially groundless. 'The memoirs 

 of the museum,' referred to, contain, among its vol- 

 umes, a work entitled ' The climatic changes of 

 later geological time, by J. D. Whitney,' and this 

 is the only ground presented by Mr. Marcou 

 for the charge he makes. Mr. Whitney's 

 work opposes accepted views on ancient glacier dis- 

 tribution, and therein opposes Agassiz, and nearly 

 all geologists living ; but he has not a word of dis- 

 paragement for Agassiz, and gives no just cause of 

 personal complaint. Mr. Marcou's charge against 

 Mr. Alexander Agassiz has no other foundation, and 

 is not true to the views he holds, and has always 

 held, with regard to his father's work and discoveries 

 connected with glaciers and the 'ice-age.' The 

 memoirs of the museum of comparative zeology, 

 founded by Mr. Alexander Agassiz, and not by his 

 father, has been for some time sustained, and the 

 museum work carried on, with the grandly generous 

 outlay on Mr. Agassiz's part of several hundred 

 thousand dollars ; and he has never made the stipula- 

 tion, which the objector seems to require, that the 

 publications should contain nothing in opposition to 

 his own, or his father's opinions. 



James D. Dana. 

 New Haven, Aug. 11. 



Lacustrine deposits of Montana. 



The examination of the Gallatin valley in Montana, 

 by the writer, under the supervision of Dr. F. V. 

 Hayden, during the summer of 1885, has developed 

 some points of general interest in relation to the old 

 lake basins of that region. Dr. Hayden was the 

 first to demonstrate the fact that the western country, 

 during the tertiary period, was covered to a greater 

 or less excent with lakes, the waters of which, as the 

 tertiary period progressed, gradually changed from 

 brackish to fresh ; until in pliocene time there were 

 numerous fresh- water lakes scattered all over the 

 area of the west, from the Mississippi valley to the 

 Pacific coast. 



The first of the basins described by Dr. Hayden 

 was the one lying east of the Rocky Mountains, and 

 extending from the Niobrara River to an unknown 

 distance south of the Platte River. He estimated 

 that this lake must have occupied an area of from 

 100,000 to 150,000 square miles. To the beds depos- 

 ited in this lake the name of the Loup Fork group 

 was given ; and they were found to shade impercep- 

 tibly into an upper group, to which he gave the name 

 of Post-Pliocene, the lower strata having been 



