X 



SCIENCE 



A WEEKLY NEWSPAPER OF ALL THE ARTS A]>. '^I'ZZ 



PUBLISHED BY N. D. C. HODGES, 874 BROADWAY, NEW YORK. 



AT fBiio,. 



'•V -ijB. 





Tenth Year. 

 Vol. XIX. No. 490. 



JUNE 34, 1892. 



Single Copies, Ten Cents. 

 S3. 50 Per Year, in Advance. 



Contents. 



Aims OF Laboratory Training. Charles 



F. Mabenj 351 



Notes and News 354 



Weeds as Fertilizing Material. 



Charles F. Millspaugh 356 



Notes on Local Membracid^ and 



FuLGORiD^. E. B. Southwick. . . . 857 



The Texas Academy of Science. Dr. 



Everhart 358 



Letters to the Editor. 



Causes which Produce Cold and Mild 



Periods. C. A. M. Taber 359 



European Origin of the White Eace. 

 Dr. D. G. Brinton 360 



THE 



]ell ?e 



COMPANY. 



96 MILK ST„ BOSTON, MASS, 



Among the Publishers. 



361 



Entered at the Post-Offlce of New York, N.Y., as 

 Second-Class Mail Matter. 



Tlii.s Company owns the Letters 

 Patent granted to Alexander Gra- 

 ham Bell, March 7th, 1876, No. 

 174,465, and January 30, 1877, 

 No. 186,787. 



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 

 licensees, responsible for such un- 

 lawful use, and all the conse- 

 quences thereof and liable to suit 

 therefor. 



iVew Method of Protecting Property 

 from Lightning. 



The Lightning Dispeller. 



Price, $20 to $30.— According to size. 



The Patent Lightning Dispeller is a conduc- 

 tor specially designed to dissipate the energy 

 of a lightning discharge, — to prevent its 

 doing harm,— placing something in its path 

 upon which its capacity for causing damage 

 may be expended. 



No recorded case of lightning stroke has 

 yet been cited against the principle of the 

 Dispeller. So far as known, the dissipation 

 of a conductor has invariably protected under 

 the conditions employed. 



Correspondence solicited. 



AGENTS WANTED. 



The American Lightning Protection Company • 



United Banl< Building, Sioux City, Iowa, 



Macmillan & Co.'s New Books. 



Just published, with numerous Illustrations, 16mo, 75 cents. 



A Guide to Electric Lighting. 



FOR HOUSEHOLDERS AND AMATEURS. By S. E. Bottone, author of "Electrical Instrument-making," "Electromotors," 

 "Electric Bells," etc. With many Illustrations. Price, 75 cents. 

 A popular guide by a well-known writer, giving in clear and easily understood language the information necessary to those about to intr oduce the elec 

 trie light into their dwellings. 



2i'ew and Revised Edition, 2 vols., Svo, $8,00, 



A Treatise on Electricity and Magnetism. 



By James Clerk Maxwell, M.A. New and Revised Edition. 2 vols., Svo, J8.00. 



The Optics of Photography and Photographic Lenses. 



By J. Traill Taylor. With 68 Illustrations. 16mo, SI. 00. 



Electric Light Cables and the Distribution of Electricity. 



By SrtjART A. Russell, A.M., I.C.E. With over 100 Illustrations. 12mo, S2.25. 



The Dietetic Value of Bread. 



By John Goodfellow, F.R.M.S. 12mo, cloth, $1.50. 



The Story of the Hills. 



A Popular Account of Mountains and How they are Made. By Rev. H. N. Hutchinson, author of "Autobiography of the Earth." 

 W^ith numerous Illustrations. 12mo, cloth, SI. 50- 



A NEW MONTHLY REVIEW OF SCIENTIFIC PROGRESS. 



NATURAL SCIENCE. 



VOL. 1. 



APRIL, 1892. 



PRICE 25 CENTS EACH NUIflBER. ANNUAIi SUBSCRIPTION, $3.00. 



NO. 2. 



MACMILLAN & CO., 1 12 Fourth Avenue, New York. 



