July 



lO, i< 



>!•] 



SCIENCE. 



25 



Some years ago I saw somethitig similar in an eastern State. A 

 hemlock tree, two feet in diameter, iiad a small streak of bark 

 taken off one side from the top down for ten or twelve feet, and 

 then the whole body of the tree was shattered, and as much as 

 six feet of it scattered in every direction, and the top was left 

 standing erect on the stump. There were no marks on the tree 

 below the splintered part. 



In both cases there seemed to be no evidence of cracks or de- 

 fects previous to the explosion. P. J. Fabnswoeth. 



Clinton, Iowa, June 28. 



The Relations of the Eastern Sandstone of Keweenaw Point 

 to the Lower Silurian Limestones. 



One of the assistants (Mr. W. L. Honnold) of the Michigan 

 Geological Survey has been engaged in the study of the relations 

 of the limestone west of L'Anse to the eastern or supposed Potsdam 

 sandstone of the copper-bearing range. This locality is described 

 in Jackson's Report (1849, pp. 399, 452), Foster and Whitney's Re- 

 port (part 1., 1850, pp. 117-119), and in Rommger's Report (1873, 

 I. part 3, pp. 69-71) ; and the limestone considered from its fossils to 

 be Trenton or some adjacent Lower Silurian strata. It was in- 

 ferred by Jackson that tlie limestone underlies the sandstone, but 

 by tlie other observers that it overlies it, although no direct con- 

 tact was seen. 



Excavations made by Mr. Honnold's party and reported by him 

 have developed the contact of the two formations, and show that 

 the two form a synclinal or oblong basin-shaped fold, with the 

 limestone overlying, and in direct contact with the sandstone. 

 The existence of this fold in the sandstone, as well as in the lime- 

 stone, removes the difficulty previous observers have had in i-econ- 

 ciling the obviously tilted limestone with the supposed horizontal 

 sandstone, and proves that the eastern sandstone exposed here is 

 of Lower Silurian age, and older than this limestone. 



At the point of contact of the two formations, exposed by ex- 

 cavation, the sandstone and limestone appear to be conformable, 

 and they are seen to constantly agree in dip and strike. The con- 

 tact between the two formations is abrupt, without any beds of 

 passage, although the upper layers of the sandstone contain con- 

 siderable carbonate of lime and magnesia, and the lower layers 

 of the limestone much silica. 



These observations are considered to be confirmatory of the com- 

 monly received view of the Potsdam age of the eastern sandstone ; 

 while the contorted state of the sandstone, extending at least a 

 mile and a half west from the limestone locality, may have weight 

 in deciding the relative age of the eastern sandstone and the 

 copper-bearing rocks. 



A careful study of the fossils will be made and additional field 

 work done, when the results will be published in detail. 



M. E. Wadswoeth. 



Michigan Mining School, Houghton, July 3. 



AMONG THE PUBLISHERS. 



The J. B. Lippincott Company announce as in press, " Harmony 

 of Ancient History," by Malcolm Macdonald; "Chambers's En- 

 cyclopaedia," Vol. "VIII. (entirely new edition, revised and rewrit- 

 ten); "The Chemical Analysis of Iron," by Andrew Alexander 

 Blair (new edition); and "A Hand- Book of Industrial Organic 

 Chemistry,'' by S. C. Sadtler. 



— "Whatever else we may think of this Russian censorship," 

 says a writer in the Pall Mall Budget, " it must at least be ad- 

 mitted that its offlcialls do their work conscientiously. A few 

 copies of Miss Hawker's ' Mademoiselle Ixe ' were recently posted 

 to various addresses in Russia. Thsy are now coming back to the 

 senders with the word Defendu stamped on their covers. One of 

 these returned copies now lies before me. Its leaves are cut from 

 end to end, and evidently the book has been handled and read. 

 Moreover, on turning over the pages, I find red pencil marks 

 placed at various passages in the earlier part of the story. After 

 a time they stop. The censor saw, I suppose, that it was a clear 

 case for prohibition, and did not trouble to score the obnoxious 

 sentiments any further. It is a compliment, however, to tlie 



authoress that he read the story to the end — as I judge by marks 

 of another kind." 



— Dr. Paul Carus has issued, through the Open Court Publish- 

 ing Co. , a new edition of his " Fundamental Problems." The body 

 of the work is not altered much; but an appendix of a hundred 

 pages is added, in which the author enters into a quite extended 

 discussion of some of the questions that the book raises, and replies 

 to some of his critics. Those who agree with his general views on 

 philosophy he treats with respect, though stoutly maintaining his 

 own views in opposition to others; but those who have attacked his 

 fundamental principles he treats testily and with scant courtesy. 

 His doctrine is in no respect modified in the new edition, but re- 

 mains the same rank materialism as before — a materialism not in 

 the least disguised by calling it "monism." It is stated, too, in 

 the same dogmatic language, in the new edition as in the old, thus : 

 "It is undeniable that immaterial realities can not exist. The 

 thing exists by its being material" (p. 86). Dr. Carus's book will 

 doubtless please those of his way of thinking ; but it will do noth- 

 ing towards converting any one who holds opposite views. 



— Leach, Shewell, & Sanborn, of New York and Boston, have 

 just published " The Number-System of Algebra," by Professor 

 Henry B. Fine of Princeton. The theoretical part of the book is 

 an elementary exposition of the nature of the number-concept, of 

 the positive integer, and of the "four artificial forms of number 

 which, with the positive integer, constitute the ' number-system ' 

 of algebra, viz., the negative, the fraction, the irrational, and the 

 imaginary." The point of view of the author is the one first sug- 

 gested by Peacock and Gregory, that algebra is completely defined 

 formally by the laws of combination to which its fundamental 

 operations are subject : that, speaking generally, these laws alone 

 define the operations ; and that the operations define the various 

 artificial numbers, as their formal or symbolic results. The his- 

 torical part of the volume contains a review of the history of the 

 most important parts of elementary arithmetic and algebra. 



— No. 38 of the Scovill Photographic Series, just published, is 

 "Photographic Reproduction Processes," by P. C. Duchoohois (New 

 York, Scovill & Adams Co., $1.) It makes a neat octavo volume 

 of 131 pages, and is a practical treatise on photo-impressions with- 

 out silver salts, for the use of photographers, architects, engineers, 

 draughtsmen, and wood and metal engravers. The author de- 

 scribes, in language readily understood by both amateur and 

 professional, all the processes employed to reproduce plans, designs, 

 engravings, cliches on paper, wood, glass, and metal plates ; be- 

 sides giving a complete description of the uranotype, analine, 

 platinotype, and improved carbon processes. The authors quoted 

 are almost " legion," but the quotations are judiciously made ; 

 and as the point in view is to show results, as well as how to 

 achieve them in the most direct way, the quotations are of im- 

 mediate benefit to the reader without detracting in the slightest 

 from the credit due the person quoted from, due credit being given 

 in each instance. 



— A recent issue of the Johns Hopkins Press is a pamphlet on 

 the " Public Lands and Agrarian Laws of the Roman Republic," 

 by Andrew Stephenson. It begins with a brief account of the 

 land belonging to early Rome, the Ager Romaniis and the Ager 

 PiMicus, followed by a general description of the Roman colo- 

 nies, whose history is inseparably bound up with that of the land. 

 The author then proceeds to describe in considerable detail the 

 various agrarian laves, from the Lex Cassia to the establishment 

 of the empire. To give a thoroughly satisfactory account of the 

 Roman land laws apart from the general history of the republic 

 is hardly possible ; but, allowance being made for that drawback, 

 Mr. Stephenson's work is worthy of praise. It is somewhat dry in 

 style, but it gives evidence not only of a careful study of the facts 

 but of a good deal of thinking about the facts. We like in par- 

 ticular the care with which the author expounds the character 

 and meaning of the various laws under review, the circumstances 

 which led to their enactment, and the actual effect they had. Mr. 

 Stephenson informs us in his preface that this monograph is in- 

 tended, not merely as a study in Roman history, but also as the 

 precursor of a book on agrarian movements in recent times and in 

 nations nearer home. 



