SCIENCE. 



[Vol. XIV. No. 338 



Sprague £lectric Railivay and Motor Company. 



Bearings Self Oiling, 

 NON-SPARKING IN OPERATION. 



Lightest Weight Consistent with 

 Highest Efficiency, 



SIMPLE IN CONSTRUCTION, 



Not Liable to get out of Order. 



Commutator Wear Reduced 

 to a Minimum, 



16 and 18 BROAD STREET, NEW YORK. 



S 



OM ETH I NG N E 



IN BOTH 



Life and Accident Insurance. 



'pEN-PAYMENT ACCIDENT POLICIES.— Insuring against Accident up to 70 years 

 of age, and if desired, returning amount of premiums to in%ureci. 



ANNUITY LIFE POLICIES. — The OLly form issued which furnishes a regular income 

 and the lowest in premium rate. 



Butli ForiiiM Cop) rigrhted, and ii!>cd exclusively by 



THE TRAVELERS, 



OF HARTFORD, COTSTlsr. 

 What the public think of them is shown by ihe 



X. ^^ I?, a- IE iBTxsiisrEss 



OF- ■'•"''jc,.,,. ««-ONTHS. 



ACCIDENT PREMIUMS, over SI,uuu;^'''«''/;;i;^^^W'''URANCE WRITTEN, 

 largely In excess of correspondins ^'"-''f J of 1888. 



Assets, $10,992,000. - - Surplus, $2,248,000. 



PAID POIilCV-HOLDERS OVER )sl6,500,000. 



JAMES G. BATTERSON, President, RODNEY DENNIS, Secretary. 



JOHN E. MORRIS, Assistant Secretary. 



Readers of Science 



Corresponding with or visiling Advertiser, 

 will confer a. great favor by mentioning this pape 



Old and Rare Books. 



One Million Magazines. Back numbers, vols. 



and sets — old and new. Foreign and American. 



CATALOGUE UPON APPLICATION. 



A. S. CLARK, 



34 Park Row, New York City. 



I ACK NUMBERS and complete sets of leading Mag- 

 i azines. Rates low. A.M. MAG. EXCHANGE, 

 Schoharie, N.Y. 



REMOVAL. 



After Monday, July i, 1889. my dental office will be at 

 6 Somerset Street (ist left from Beacon), until further 

 notice. My Flesh-brushes will be for sale there. All in- 

 formation in regard to the Flesh-brushes, also instruc- 

 tions for using the same, can be obtained at the new 

 'office, from g 30 to 10.30 a m.. and from 4 to s pm. 

 Communications by mail promptly replied to. 



Boston, Mass. OKO. F. WATERS. 



FOOD 



ADULTERATION 



And its Detection. With photomicrograph ic plates and 

 a bibliographical appendix. Ey J. P. EattershaU. 328 

 pages, 8vo, cloth. Price, S3. 50. Circulars ami Catalogues 

 on application. K. & F. N. SPON. 



12 Conlandt St., New York. 



Schools, 



Con- 



Ne 



Ha 



MRS. CADY'S SCHOOL FOR YOUNG LADIES. 

 Prepares for Smith and Wellesley, and admits to 

 Vassar by Certificate. Circulars. Early application 

 necessary. 



Indiana, Terre Haute. 



ROSE POLYTECHNIC liSTSTITUTE.-A School 

 of Engineering. Wei! endowed,well equipped depart- 

 ments of Mechanical and Civil Engineering. Electricity, 

 Chemistry, Drawing. Extensive Shops & Laboratories. 

 Expenses low. For catalogue address T. C. Mendenhall, 

 Pres. _ ^_^_^„_„_______ 



Michigan. Houghton. 



MICHIGAN MINING SCHOOL. — For Catalogues 

 address M. E. Wadsworth, A.M., Ph.D., Director. 



THE 



liciiii \i Ti 



COMPANY. 

 98 MILK ST., BOSTON, MASS, 



Tliis Coinpany owns the Letters 

 Patent granted to .Alexander Gra- 

 ham Bell, March 7tli, 1876, No. 

 174,465, and January 30, 1§77, 

 No. 1§6,7§7. 



The Transmission of Speech by 

 all known forms of ELECTRIC 

 SPEAKING TELEPHONES in- 

 fringes the right secured to this 

 Company by the above patents, and 

 renders each individual user of tel- 

 ephones, not furnished by it or its 

 licensee.*, responsible for i-uch un- 

 lawful use, and all the conse- 

 quences thereof and liable to suit 

 therefor. _^_^__ 



ESTERBROOK'S 

 STEEL PENS. 



OF SUPERIOR AND STANDARD QUALITY. 

 Leading Nos.; 048, 14, 130, 135, 239, 333 



For Sale by all Stationers. 



THE ESTERBROOK STEEL PEN CO., 



Works: Oamden. N.J. -16 Joliu St.. >'etv York. 



PATENT ill* "■■■ 



Patent F<Kket Tan N v. 



% 



J THE WORLD. ^gTI 



;goldmepal3 



L scd by thousai 

 IP h mica and by 

 rere is FuUmao Palace Car Co., 

 . lason & Hamlin t>Kan and Pi3n» 



Repairs Everything. 



Itssucces has brought a lot of Q 

 Im tatora c 

 &ble. 



TL . . 



iactured solely by the fl 



RUSSIA CEMENT CO., 



LOUOESTER, MASS- 

 Send 1(K\ and dealers' card who || 

 w^n t ktvp il in atock, fw sample, f 



