June 30, 1893.] 



SCIENCE. 



363 



golian. The author does not mean to imply that our Indians are 

 strictly Mongolians, or that America has been populated from 

 Asia, for he says '' the American race is, somatologically speak- 

 ing, not a type, but has characteristics which can only be called 

 Mongoloid." F. W. Hodge. 



Washington City. 



Lahtrratory Calculation and Specific-Oravity Tables. By John 

 S. Adriance, A.m. Second editon. New York, John 

 Wiley & Sons. Interleaved. 114 p. 

 In some respects the author has in this second edition given us 

 a new book, having enlarged the original tables and added others 

 of importance. This increase of substance has, too, a value of its 

 own in works such as these, being of far greater importance here 

 than similar additions in general and descriptive works, for not 

 only is the reputation of a book of tables based upon the accuracy 

 of the figures, but also largely upon its completeness. We have 

 all relied more or less upon like works for aid in laboratory cal- 

 culations, and yet when certain data are found absent, how soon 

 the book will fall into disuse entirely and make its way to the 

 top shelves ! Mr. Adriance, however, himself a consulting chem- 

 ist and fully alive to the necessities of the case, has chosen not 

 only such tables as are in constant use, but also those of frequent 

 or less frequent need, covering extraordinarily well the field of 

 ordinary chemical analysis. Such a work as this is of true assis- 

 tance, and despite the claim urged by some chemists as to the 

 possible introduction of error when using "ready-made results," 

 we believe the chance of error to be greater when these same re- 

 sults have to he calculated under the strain of physical fatigue, 

 following a long day or night of analytical or experimental work. 

 Naturally all tables of factors, and all data of this kind, should 

 be proven in moments of leisure, and in important cases, notably 

 those involving legal testimony, they should be thrown aside 

 altogether; but for daily use in the laboratory, they are invalua- 

 ble in the saving of time and mental labor. Not only is the sub- 

 stance of the book " good," but in appearance it is neatness it- 

 self, each word and figure is clear-cut and distinct, an element 

 highly important in tabular statements. The book is interleaved 



and ample opportunity thus given the chemist for additions and 

 remarks C. P. 



Chemical Theory for Beginners. By Leonard Dobbin, Ph.D., 

 and James Walker, Ph.D., D. Sc, Assistants in the Chem- 

 istry Department, University of Edinburgh. London and 

 New York, Macmillan and Co., 1892. 240 p. 

 Of the vast number of text-books bearing upon chemistry, we 

 have but few treating of its foundation or theory. The smaller 

 works merely touch upon theoretical discussion, while the larger 

 treatises presuppose an extensive knowledge of the same. It is 

 then a fact that only those students with the advantages of able 

 instruction and scientific associations arrive at a really clear un- 

 derstanding of the ground-work of chemical notation, reaction 

 and law. " Students enter the laboratory at once," is a familiar 

 phrase in many college announcements, and there are excellent 

 arguments for such a custom, provided a thorough study of 

 theory accompanies the practical demonstration. More often, 

 however, in general science courses the theory is disposed of in 

 one or two brief lectures, all effort being concentrated upon a 

 rapid advance into the field of "the elements, their compounds, 

 their characteristics and reactions." 



The above work is, we believe, rather unfortunately named, for 

 while it will be easily understood by a beginner, and is a most 

 excellent book for such a one, still it can and will be read advan- 

 tageously by many advanced students and practical chemists. 

 The wording is smooth and attractive, always interesting, never 

 fatiguing; the student is carried forward, by an easy and natural 

 progression, from the nature of things to a study of chemical ac- 

 tion, of combustion, the laws of Boyle, Charles, and Avogadro, 

 of density and of the atomic weights. Chemical notation is not 

 reached until the l^th chapter, where, with the knowledge already 

 gained, its discussion is of value and intelUgible to the beginner. 

 The later chapters contain an entirely non-mathematical exposi- 

 tion of the more important principles of general chemistry re- 

 viewed in the light of recent research, treating of the kinetic 

 molecular theory, mass action, solution, electrolysis equivalence 

 the periodic law, etc. C. P. 



Delicious 



Drink. 



Horsford's Acid Phosphate 



with water and sugar only, 

 makes a delicious, healthful and 

 invigorating drink. 



Allays the thirst, aids diges- 

 tion, and relieves the lassitude 

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Dr, M. H. Henry, New York, says: 

 "When completely tired out by pro- 

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 erage it possesses charms beyond any- 

 thing I know of in the form of medi- 

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Descriptive pamphlet free. 

 Rumford Chemical Works, Providence, R, I. 

 Beware of Substitutes and Imitations. 



Exchanges. 



[Freeof charge to all, if of satisfactory character. 



\ddres5 N. D. C. Hodges, 874 Broadway, New York.l 



For sale at low price. — A fine old-fashioned photo- 

 graphic camera, rosewood box, one foot square, 

 lenses, four inches diameter, made by C. C. Harri- 

 son. Plateholders, troughs, baths, etc., all in large 

 wooden case, formerly the property of the late 

 President Moore, of Columbia College. This is a 

 fine example of an instrument of the best make for 

 the old wet-process methods, and valuable to any 

 institution 01 amateur interested in the history of 

 photography in the V. S. Address M. S. Daniel, 

 236 W. 4th St., New York. 



I wish to exchange a collection of 7,000 shells, 

 1001. species and varieties, American and foreign, 

 land, nuviatile and marine, for a good microsome 

 and accessories. Address, with particulars, Dr. 

 Lorenzo G. Yates, Santa Barbara, California. 



For exchange. — I wish to exchange Lepidoptera of 

 South Dakota and other sections, for Lepidoptera 

 of the world. Will purchase species of North Amer- 

 ica. Correspondence solicited, particularly with 

 collectors in the Rocky Mountains, Pacific coast 

 and Hudson's Bay regions. P. C. Truman, Volga, 

 Brooking county. South Dakota. 



For sale. — Wheatstone Bridge wire, made to 

 order, new and unused. Price, $10. W. A. Eobbe, 

 Fortress Monroe, Va. 



For sale or exchange. — One latest complete edi- 

 tion of Watt's Dictionary of Chemistry, in fair con- 

 dition; one thirty volume edition (9th) of Allen's 

 Encycloptedia Britannica, almost new. Will sell 

 cheap for cash or will exchange for physical or 

 chemical apparatus. Address Prof. W. S. Leaven- 

 worth, Ripon College, Ripon, Wis. 



Exchange. — One celestial, one terrestrial globe, 

 one lunatettis and charts, celestial maps, diagrams 

 and ephemeris from 1830 to 1893, astronomical 

 works, all in good condition. Will sell cheap or ex- 

 change. Make offer. C. H. Van Dorn, 79 Nassau 

 St., New York. 



The Eev. A. C. Waghome, New Harbor, New- 

 foundland, wishes to sell collections of Newfound- 

 land and Labrador plants, all named by competent 

 botanists. He is going on a missionary journey 

 along the Labrador coast, from the middle of July 

 till October, and in return for much needed aid to- 

 wards (Episcopal) Church purposes in that region, 

 will be ^lad to be of service to any botanists who 

 may write to him. Letters posted in the U. S. up 

 to July 1 will reach him at the above address, and 

 if posted later will be forwarded. 



Wanis. 



A GRADUATE of an American Polytechnic insti- 

 tution and of a German university (Gottingen) 

 seeks a position to teach chemistry in a college or 

 similar institution. Five years' experience in 

 teaching chemistry. Address Chemist, 757 Cary St 

 Brockton, Mass. *' 



AN experienced teacher in general biology wishes 

 a position in a first-class college or university 

 Three years in post-graduate study. Extensive 

 experience. Strong indorsements. Address E W 

 Doran. Ph.D., 1327 5 St., N. W., Washington. D. C. ' 



THREE teachers wanted for a male and female 

 seminary in central New York. Typewriting, 

 etc., languages, mathematics, sciences, et. al. Send 

 stamp with and for particulars. Box 701, Hemp- 

 stead, L. I. 



A ZOOLOGICAL collector and taxidermist of ten 

 years' experience in the Held is now open to en- 

 gagement, for either field or laboratory work 

 References furnished. Address Taxidermist, Box 

 75, White Sulphur Springs, West Va. 



WANTED.— A set of Allen's Commercial Organic 

 Analysis, 4 vols. Vols. I. and II. particularly 

 desired. Condition not important, all leaves being 

 present and in place. Address Charles Piatt, M 

 Lewis Block, Buffalo. 



WANTED, as principal of a flourishing technical 

 school, a gentleman of education and experi- 

 ence who will be capable of supervising both me- 

 chanical and common school instruction. Special 

 familiarity with some technical branch desirable 

 Address, giving age, qualifications, etc.. J. B. Bloom- 

 ingdale. Fifty-ninth street and Third avenue N Y 



IITANTED.— A young man as assistant in our 

 VV microscopical department. Queen & Co., 

 Philadelphia. 



THE undersigned desires specimens of North 

 American Gallinae in the fiesh for the study of 

 their pterylosis. These species are especially de- 

 sired: Colinus ridgu-ayi. cyrtonyx viontezumae, 

 deudragapusfranklini. lagopus welchi.tympanuchus 

 cttpido and pedioecefes phasianelhis. Any persons 

 having alcoholic specimens which they are willing 

 to loan or who can obtain specimens of any of the 

 above are requested to communicate with Hubert 

 Lyman Clark, 3922 Fifth Avenue, Pittsburgh, Pa 



