January 13, 1893.] 



SCIENCE. 



27 



•connection between the undeniably interesting facts related and 

 ithat " material connection " between the bodies of our universe, 

 which he claims to have discovered. Whatever may be the real 

 -nature of that connection — and we doubt if our author has hit 

 upoii it — these facts will, unquestionably, be found perfectly con- 

 sistent with it, and a part of it; but a thousand other schemes 

 than this may be produced by the poetic imagination of the ama- 

 teur in science into which these facts may be also worked, and it 

 remains, most likely, tor direct investigation, with all the aid of 

 the most perfect modern apparatus and methods, to finally de- 

 termine solutions of the still numerous problems of contemporary 

 science. The Greek methods of speculation and noo-scientiSc 

 imagimtion are not of much promise where a " material connec- 

 tion ■' between the bodies of the solar and other systems of the 

 universe is the subject-matter of investigation. The machinery 

 of the universe must probably be ultimately revealed by expert 

 and practised mechanicians. 



Dynamics of dotation. By A. M. Worthington. London, 

 Longmans & Co. 1893. 155 p. 12°. 

 A LITTLE book on a very elementary portion of the science of 

 mechanics, as here treated, but an excellent treatise for begin- 

 ners. Professor Worthington has made his process of instruction 

 a most practical and sensible one — giving first a statement of the 

 facts and data as developed by experiment and then deducing the 

 laws of mechanics applying to the case and finally applying those 

 laws and the equations expressing them to the solution of prob- 

 lems. Such applications are well illustrated by considerable 

 numbers of well-chosen examples. This method of treatment is 

 certainly well suited to the instruction of young students, and we 

 are not sure that it is not the best for older ones in many cases in 

 which the opposite course of enunciating the law and later illus- 

 trating it and deducing constants by experiment. We observe 

 that the new term, "torque," is accepted by the author and that 

 he also adopts the "poundal" and the conventional distinction 



pound for force and lb. for mass. We are not sure that either is 

 needed or desirable ; but fashion and convention have almost as 

 much influence in science as in modes de Paris. They have 

 probably come to stay, like the barbarous nomenclature of the 

 electricians; but, in this book, the frequent use of the "engi- 

 neers, or gravitation" units, as its author calls them, will go far 

 toward relieving the mind of its readers of those misapprehensions 

 and confusions which so constantly arise in the study of the older 

 text-books. 



Mechanical Drawing. By C. W. McCoRD, A.M., Sc.D. New 

 York, J. Wiley & Sons. 345 p. 4°. 

 Tras large and handsomely made book contains the line of work 

 proposed for use in the elementary instruction of the technical 

 schools, especially those of engineering. The exercises given are 

 those which have proved successful, during twenty years of 

 work, by its author. They are intended to train eye, hand, and 

 judgment as well. "The artidcial and often useless stage ma- 

 chinery of descriptive geometry" is kept out of sight as far as 

 possible, although they are not considered entirely useless, never- 

 theless. Maxims, bits of condensed wisdom, are sprinkled 

 throughout the work, as "Pencil lightly," "Pencil clearly," 

 " Make haste slowly," and are clearly themselves the result of 

 long experience and a fruitful observation. The methods are ex- 

 cellent, the manner of doing the work no less satisfactory; and 

 the whole constitutes one of those rare treatises on a technical sub- 

 ject which can only be produced by an author who is wise in the 

 principles of his craft and experienced, practically, in their appli- 

 cation to the actual, live problems of the profession in which he 

 is an expert. The principles of projection, the laying-out of 

 curves, and the construction of problems in connection with the 

 design and adaptation of gearing to its work, illustrate especially 

 this advantage possessed by the author in the present case. This 

 is an admirable work, and author and publishers are alike enti- 

 tled to great credit. 



Dr. T. H. Andrews, Jefferson 

 Medical College, Philadelphia, says of 



Horsford's Acid Phosphate. 



"A wonderful remedy which gave me 

 most gratifying results in the worst 

 forms of dyspepsia." 



It reaches various forms of 

 Dyspepsia that no other medi- 

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 the weakened stomach, and 

 making the process of diges- 

 tion natural and easy. 



Descriptive pamphlet free on application to 

 :Runiford Chemical Works. Providence, R. I. 



Beware of Substitutes and Imitations. 



For sale by all Druggists. 



Exchanges. 



[Freeof charge to aU, if of satisfactory character. 

 Address N. D. C. Hodges, 874 Broadway, New York.l 



The undersigned has the following specimens to 

 exchange for crystals of any eastern or foreign lo- 

 calities or Indian relics: tin ore, metacinnabarite, 

 stibnite, garnierite, calenanite, hanksite. uiexite, 

 rubellite, lepidolite.blue and green onyx, Cat. pine- 

 ite, aragonite on chalcedony, cinnabar, dout)le re- 

 fracting spar, clear and clouded, and others. J. R. 

 Bush, care of General Delivery, Los Angeles, Cat. 



For sale or exchange. — A private cabinet of about 

 200 species of fossils, well distributed geologically 

 and geographically, Silurian, about 40; Devonian, 

 about 50; Carboniferous, about 80; others, about 30. 

 Frank S. Aby, State University, Iowa City, la. 



For exchange — Minerals, fossils, F. W. shells, 

 land shells, native woods, Indian relics, two vois. 

 of Smithsonian reports, odd numbers of scientific 

 magazines, copper cents, etc., for good minerals 

 not in my collection, good arrow- and spear-heads 

 and natural history specimens of all kinds. Cor- 

 respondence solicited with list of duplicates. G. 

 E. Wells, Manhattan. Kan. 



For sale or suitable exchange. — A spectrometer 

 made by Fauth & Co., Washington, D. C., according 

 to the plan of Prof. C. A. Young. This instrument 

 is suitable for the most advanced investigations 

 and determinations. Cost originally S700 and has 

 been used but little. WUl be disposed of at a con- 

 siderable reduction. Address Department of Phys- 

 ics, Ohio University, Athens, O. 



I will send British land and fresh-water shells in 

 return for those of America, any part, sent to me. 

 I have at present about fifty or sixty species, with 

 many varieties. W. A. Gain, Tuxford, ISfewark, 

 England. 



The Biological Department of Hamline University 

 desires to offer microscopic slides of animal tissues, 

 or whole animals, in exchange for first-class fossils. 

 Address correspondence to Henry L. Osborne, Ham- 

 line University. Ffamline, Minn. 



Wants. 



WANTED.^American Journal of Conchology, 

 seven volumes. Parties having these for 

 sale will please address the undersigned, stating 

 condition and price. R. Ellsworth Call, Louisville, Ky. 



A GRADUATE ENGINEER will give instruction 

 evenings in geometry, trigonometry and sur- 

 veying, mechanics, physics, mechanical drawing 

 and general engineering construction. Five years' 

 experience in field and editorial work on engineer- 

 ing journal. References furnished. C. S. fl., 103 

 Tribune Building, New York. 



A POSITION is desired in the South, preferably 

 j\ the Gulf States, where I can teach tlie sciences 

 Can also iLStruct in other branches. Salary only 

 nominal, as I am simply desirous of employment 

 while spending the winter in the South. A private 

 family preferred, but will acceot regular school 

 work if nottoo confining. MORRIS GIBBS, M.D., 

 Kalamazoo, Mich. 



WANTED. — By well - qualified and experienced 

 science master and associate of the Royal 

 School of Mines, London, aged 26 (at present in 

 England), a mastership m technical college or uni- 

 versity for any of the following subjects: Engineer- 

 ing sciences, geology and mineralogy, physics, chem- 

 istry and metallurgy, etc.. etc. Can provide excel- 

 lent references and credentials. Apply. J. G., 17 

 Sussex St., Rochdale, England. 



A GRADUATE of the University of Pennsylvania 

 and a practical mineralogist of twenty years' 

 experience desires to give his services and a cabi- 

 net of 2.5,(00 specimens, all named, with about the 

 same number of duplicates, in minerals, crystals, 

 rocks, gems, fossils, shells, archaeological and ethno- 

 logical specimens and woods to any institution de- 

 siring a fine outfit for study. The owner will in- 

 crease the cabinet to .50,000 specimens in two years 

 and will act as curator. Correspondence solicited 

 from any scientific institution. J. W. Hortter, 

 M.D., Ph.D., San Francisco, Cal., General P. O. 

 Delivery. 



The American Geologist for 1893. 



Edited by Prof. S. Calvin. University of Iowa; Db. E. W. Claypole, Buchtel College; John Eterman, 

 Lafayette College; Dr. Persifor Frazer. Penn. Hort. Soc; Prof. F. W. Cragin. Colorado College; 

 Prof. Rob't T. Hill, U. S. Irrigation Survey: Dr. Andrew C. Lawson, University of California; Frank 

 D, Knowlton, U. S. National Museum; Joseph B. Tyrrell, Geol. Sur.ot Canada: E. O. Ulbich. Minnesota 

 Geological Survey: Prof. I. C. White. University of West Virginia: Prof. N. H, Winchell, University 

 :>f Minnesota. Now in its Xih volume. S3-50 per year. Sample copies. 20 cents. Address 



THE GEOLOGICAL PUBLISHING CO., MinneapoUs, Minn. 



