SCIENCE. 



[Vol. XI. No. 282 



Just Published. 



Salomon's Management of 

 Accumulators, 



and Private Electric Light Installation. Third 

 edition. Revised and Enlarged. i2mo, cloth, 

 .fl.20. 



Bottone Electrical Instrument 

 Making for Amateurs, 



A Practical Hand-Book, with 48 illustrations. 

 I2ino, cloth, $1.20. 



Kennedy Electrical Distri- 

 bution by Alternating 

 Currents 



and Transformers. 8vo, 80 cents. 



Badt Dynamo Tender's Hand- 

 Book, 



with 70 illustrations, $1.00. 



D. VAN NOSTRAND, Publisher, 



23 Murray and 27 Warren Streets, N.Y. 



I^^Copies sent by mail post-paid on receipt of 



Schools. 



THE BEBLITZ SCHOOL OF LANGUAGES. 



SUMMMER COURSE 



AT ASBURY PARK, N. J., AND AT OLD ORCHARD BEACH, ME. 



The Berlitz Method is acknowledged by nil first-class American and European authorities as ihe best of all na- 

 1 methods. Instruction will be given by iherejiular professors of the Berliiz Schools, where only the best of 

 ve teachers are employed. Their long experience and unparalleled success in teaching languages will make ihcir 

 ruction highly interesting and eminently practical. The course consists of niimerous lessons, lectures, excursions, 

 a continual practice in French and German conversation. The terms are very low. A special course for teach- 



For sample pages of the French and the German book^, circulars, etc , apply to 



BERLITZ & CO., W. Madison Square, N.Y. 



HARVARD UNIVERSITY. 



'ill be given in the folio 

 ■ of] — 



subjects during 



Botany, Chemistry, French. German, Geology, History, 

 Physics, Physical Training, Topography. 



For information apply to the Secretary of Harvard 

 Utiiversiiy, Cambridge, Mass. 



New York, Koslyn. Long Island. 

 'pIIE BRYANT SCHOOL. — A BOARDING 

 •*• school of the highest class for boys. Primary, In- 

 termediate and Academic Departments ; thorough Mili- 

 tary Organization and Discipline, with Systematic Phys- 

 ical Training. School property lepresenting an outlay of 

 over $250,000 ; one of the finest in the United States, in 

 proximity to country-seat of the laie William Cullen Bry- 



SUMMER SCHOOL FOR BOYS. 



June 21SC to September ist. 



" The best located and most successful of the Slimmer 



Schools for Boys. Scliool property beautifully situated 



on salt water. Every facility for study 



For ■ ' ■ • 



New York. PeekskiU. 

 'UMMER SCHOOL FOR BOYS. — PEEKSKILL 

 > Military Academy, June 20th to September 5th, '88. 

 nd lor circular. 



John N. Tilden. A M., M.D., Peekskill, N.Y. 



POLITICAL 

 CYCLOPEDIA. 



Edited by JOHN J. LALOR. 



The only work of its kind in the English Lan- 

 guage, supplementing all other Cyclopadias, and 

 covering a most importiint field, hitherto unoccu- 

 pied. 



JAMES G. BLAINE 



writes, " / use it almost daily fur reference, and 

 regard it as a model." He refers to the POLIT- 

 ICAL CYCLOPEDIA, of which the Atlanta 

 Constitution .says, "Is is dazibtfoit, indeed, if 

 a more important work of reference has ever brcn 

 p7-epared," and the New York Nation adds, 

 "W liniely and valuable aid to political education. 

 We caintot withhold t>ur warm commendation of 

 the industry and discrimination of the editor, 

 and the enterprise of the publishers." 



If you wish to think, speak, and act intelligently upon 

 the ereat questions of the day, you need this work, writ- 

 ten by the most eminent specialists in this country and 

 Europe ; e. ^., DAVID A. WELLS discusses the ■fariff 

 and Tariff Legisiatio't from the standpoint of the free- 

 trader, and D. H. MASON from ihe point of view of the 

 protectionist; E. L GOViVAlA -n-ntisoi Offici-Holde^s; 

 PROF. ALEX. JOHNSTON the articles on the Politi- 

 cal History of the United States; DORMAN B. 

 EATON, of Civil Service Reform : PRES. D. C. GIL- 

 MAN, of Universities: SIMON STERNE, of Rail- 

 roads: PkES. F, A. WALKER, of Public Reveime 

 and Wages: EDWARD ATKISON, of Banks: JOHN 

 J. KNOX, of the Currency, etc.; THOMAS M. 

 COOLEY, Pres. Interstate Commerce Commission, of 

 The Bar, Law 0/ Corporations, etc.; H. C. BUR- 

 CHARD, ex-Director of the Mint, of Coitiage, Gold, 

 Silver. Currency, etc. If you wish to know all about 

 it. send to the publishers for their 16-page descriptive 

 pamphlet, which they send free to any address in the 

 United States. They want more good agents. Address 



CHARLES E. MERRILL k CO., 



PUBLISHERS, 743 BROADWAY, N.Y. 



AT MOQNT HOPE LADIES SEMINARY, 



Takkytown-on-the-Hudson, N. Y., 

 $300 pays board and tuitions per school year. Mu 

 and art only extras. Beat advantages with home ca 

 Opens Sept. 26th. 



ROBT. C. FLACK. A.M., Principal. 



TWriSS HOGARTH'S SCHOOL FOR GIRLS. - 

 Goshen, Orange Co. N.Y. 

 The ninth year will begin Sept. 5, 1S88. Tho 

 instruction in English, Latin, French, German, Ar 

 Music. Special Attention to health and good ma 

 and to the development of practical common sense. 



Massachusetts. Boston, 152 Huntington Avenue. 

 TWrME. E. DECOMBES' FRENCH AND ENG 



i: u Tj o_i 1 f._ -:- girls^ opens Septemberig, 



ras. Highest References. 



li.h Home School fo: 

 Siooo per yeai 



No! 



Massachusetts, Waverley, 

 C ELECT HOME SCHOOL FOR YOUNG LADIES 

 *-* Seven miles from Boston, on beautiful estate of 

 twenfv-one acres. Thorough preparation for college, if 

 drsired. Backward pupils re eive special attention. 

 Address Miss L. A, HiUL, Principal. 



UNIVERSITY OF VIRGINIA SCIENTIFIC AND 

 Engineering Schools. For catalogue, address, 

 C. S. Venable, Chairman of Faculty, 



P.O., University ol Va., Va. 



TILESTON & HOLLIKGSWORTH, 



64 Federal Street, Boston. 



Manufacturers of Fine Book Papers for let- 

 ter press and cut prmting. The attention of 

 publishers and printers is called to our Ivory 

 Finish (no gloss) paper. A boon to studious 

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Teachers. 



BROCK.WAY TEACHERS' AGENCY, 

 (formerly Chicago.) 

 Supplies Superior Teachers with positions in the be; 

 Schools and Colleges. 



MRS. L. FREEMAN BROCKWAY, 



28 W. 23rd St., New York. 

 Schools recommended to parents. 



11 "ants. 



AN EDUCATED AND CAPABLE PERSON 

 wanted in everj' town and city to canvass for sub- 

 scriptions to Science : liberal compensation. Address, 

 naming references, Publisher of Science, 47 Lafayette 

 Place, New York city. 



Investments. 



GUARANTY 

 INVESTMENT COMPANY. 



70| Capital .$250,000. ^ ol 

 |o Guaranteed Farm Mortiages / 'o 



Professional men and persons 

 living upon salaries will find these 

 carefully selected mortgages the 

 very best investment for their sur- 

 plus earnings. No loan is taken 

 for more than 40^ of a conserva- 

 tive valuation, and none where the 

 value of land is not increasing. 



A Monthly BuUeiin is published giving full par- 

 ticulars about every 1. an 

 Address for circulars a d the Monthly Bulletin 



HENRY A.RILEY, 



General Eastern Manager, 



191 Broadway, New York. 



7^ FIRST MORTGAGES. 7^ 



Upon 



arefuUy selected farms in the most flourishing and 

 pidly growing parts of the West- 



6-^ 



Guaranteed Mortgages 

 Debenture Bonds 65« 



Secured by similar mortgages, and also by the capital of 

 the issuing Company. 



THE EASTERN BANKING COMPANY, 



43 MILK STREET, BOSTON. 

 Francis A. Osborn. Pres. Edxv. T. Merrihew, Treas. 



IAN 

 ITEEL PENS 



Are the Best, 



IN THE E.SSENTIAL QUALITIES <(F 



Durability, Evenness of 

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Samples for tritil of 12 difTerent 

 recein of 10 cents in stamps. ' 



IVISON. BL&KEM&N & CO.. 



tamps. A.-^U lor crj No. 8. 

 753 Rri)!i<lwny, 



