104 



SCIENCE. 



[Vol. XXII. No. 551 



On the western part of the island, where the principal 

 exposure occurs, the strata have a dip of twenty-two de- 

 grees to the southwest, reminding us that diiring the 

 period of upheaval through which this district passed. 

 Great Manitou by no means fared so well as its sister 

 island. 



On the third largest island of the group there are also 

 indications of a stratified formation, but in this case, as in 

 the other referred to, the whole is so covered with drift 

 and rubbish and densely wooded as to render it at pres- 

 ent practically indeterminable. 



The islands are not only conveniently and pleasantly 

 situated, but are also one of the most delightful and 

 healthful summer resorts in this whole northern region. 

 The student of geology will always find a seasonable visit 

 to these islands a delightful pastime, and will be amply 

 rewarded in being afforded an opportunity of studying 

 some features of geological science seldom experienced, 

 and which assist us materially in correctly interpreting 

 the past history of the earth. Some of the fossils found 

 on the islands are in themselves interesting objects of 

 study, and beautiful illustrations of that wisdom and skill 

 everywhere to be seen in the Creator's work. And while 

 they are important as evidences of past history and assist 

 in determining to some extent the very great age of our 

 world, they are also no less significant in demonstrating 

 the eternity of Him who "before the mountains were 

 brought forth, or ever the earth and the world were 

 formed," from everlasting to everlasting is G-od. 



In contemplating the glory and grandeur of the 

 Creative handiwork, and considering the great antiquity 

 of the world on which we dwell, may we not well adopt 

 the language of inspiration and say: "Grreat and mar- 

 vellous are thy works, Lord God Almighty;" "Of old hast 

 thou laid the foundations of the earth." 



THE AMEEICAN ASSOCIATION FOR THE ADVANCE- 

 MENT OF SCIENCE. 



The 42nd meeting of the American Association opened 

 at Madison, "Wisconsin, on August 17th. The following 

 were the officers of the meeting, new secretaries having to 

 be elected in the case of Sections E and G, Messrs. Hill 

 and Coville being absent on the opening of the meeting : 

 President, William Harkness, Washington, D. C. ; Vice 

 Presidents. — A. Mathematics and Astronomy — C. L. Doo- 

 little. South Bethlehem, Pa. B. Physics — E. L. Nichols, 

 Ithaca, N. Y. C. Chemistry — Edward Hart, Easton, Pa. D. 

 Mechanical Science and Engineering — S. W. Eobinson, 

 Columbus, O. E. Geology and GeograjDhy — Chas. D. 

 Walcott, Washington, D. C. F. Zoology — Henry F. Os- 

 born. New York, N. Y. G. Botany — Charles E. Bessey, 

 Lincoln, Neb. H. Anthropology — J. Owen Dorsey, Ta- 

 coma Park, Md. I. Economic Science and Statistics — 

 William H. Brewer, New Haven, Conn. Permanent Sec- 

 retary, F. W. Putnam, Cambridge (office Salem), Mass. 

 General Secretary, T. H. Norton, Cincinnati, Ohio. Sec- 

 retary of the Council, H. L. Fairchild, Rochester, N. Y. 

 Secretaries of the Sections. A. Mathematics and Astron- 

 omy — C. A. Waldo, Newcastle, Ind. B. Physics — W. Le- 

 Conte Stevens, Troy, N. Y. C. Chemistry— H. N. Stokes, 

 Chicago, 111. D. Mechanical Science and Engineering — 

 D. S. Jacobus, Hoboken, N. J. E. Geology and Geog- 

 raphy— W. H. Hobbs, Madison, Wis. F. Zoology— L. O. 

 Howard, Washington, D. C. G. Botany — B. T. Galloway, 

 Washington, D. C. H. Anthropology — Warren K. Moore- 

 head, Xenia, 0. I. Economic Science and Statistics — 

 Nellie S. Kedzie, Manhattan, Kan. Treasurer, Wiljiam 

 Lilly, Mauch Chunk, Pa. 



The addresses of the Vice Presidents were delivered 

 before their respective sections in the afternoon, and they 



were as follows : Vice President Nichols, before Section 

 of Physics; subject, "Phenomena of the Time Infinitesi- 

 mal." Vice President Dorsey, before Section of Anthro- 

 pology; subject, "The Biloxi Indians of Louisiana." Vice 

 President Walcott, before Section of Geology and Geog- 

 raphy; subject, "Geologic Time as Indicated by the 

 Sedimentary Pocks of North America." Vice President 

 Brewer, before Section of Economic Science and Statistics; 

 subject, "The Mutual Relations of Science and Stock- 

 Breeding." Vice President Osborn, before Section of 

 Zoology; subject, "The Rise of the Mammalia." Vice 

 President Doolittle, before Section of Mathematics and 

 Astronomy; subject, "Variations of Latitude." Vice Presi- 

 dent Bessey, before section of Botany; subject, "Evo- 

 lution and Classification." Vice President Hart, before 

 Section of Chemistry; subject, "Twenty-five Years' Pro- 

 gress in Analytical Chemistry." Vice President Robinson, 

 before Section of Mechanical Science and Engineering; 

 subject, "Training in Engineering Science." 



Vice President Walcott in his address before Section 

 E, Geology, referred to the various estimates that had 

 been made as to the length of geological time, these vary- 

 ing from a minimum of 3,000,000 to a maximum of 1,200,- 

 000,000 years. His own studies, based largely upon the 

 Paleozoic sediments of the Cordilleran area, gave a mean 

 between these. The following table gives the estimated 

 time for each of the larger geological eras : 



Cfenozoic, 



Mesozoic, 



Paleozoic, 



Algonkian, 



Ai'chean, 



2,900,000 



7,240,000 



17,500,000 



17,500,000 



9 



Total, - - - .$45,140,000 



He stated his belief in the theory that the deep seas 

 and the continental areas are jiermanent, and thought that 

 the main outlines of the North American continent were 

 laid down as far back as Archean time. Cambrian sedi- 

 ments on either side of the continent are of such extent as 

 to justify the belief, or rather necessitate the belief, that 

 extensive continental masses were near at hand. Thirty 

 thousand feet of sediment in the Rocky Mountain area, 

 and nearly as much in the Appalachian, were indicative of 

 long lajjses of time. The sediments of the Rocky Moun- 

 tains were deposited over an area of at least 400,000 

 square miles and jsrobably of 800,000. This area extend- 

 ed from the Gulf of Mexico to the Arctic Ocean. 



Many statements were made as to the rate of denuda- 

 tion and deposition of calcareous and mechanical sedi- 

 ments. Estimated at the rate of deposit of calcareous 

 sediments now being formed, it was calculated that about 

 600,000 years would be required to form a deposit of 

 limestone twenty-two feet in thickness. It was estimated 

 that about 47,000,000 years would be required, at this 

 rate, to form the dejDOsit of calcium carbonate in the 

 Cordilleran area. But reducing, this fifty per cent for any 

 l^ossible change of conditions, and then taking off a fur- 

 ther twenty-five per cent for special conditions affecting 

 deposition, 10,000,000 years would remain for the accumu- 

 lation of the calcareous sediments. To this must be add- 

 ed time for mechanical deposits, and putting this at its 

 lowest possible term of 1,500,000 years, we have the 

 17,500,000 years for the Paleozoic time given above. 



Professor Osborn, in addressing Section F upon the 

 rise of the mammalia, dwelt especially upon the methods 

 emploj'ed by jjaleontologists, and upon the broad gen- 

 eralizations that had been made by students of fossil 

 mammals. Among these was the generalization of Marsh, 

 that all early types of mammalia had small brain cavities. 



Cope had shown by the growth of the feet that all early 

 types had five toes upon both the fore and hind feet and 



