THE POPULAR SCIENCE MONTHLY. 



CO>T)rCTED BY 



L_ "S- O TJ 3VE -A. 3Sr S 



This periodical was started (in 18T2) to promote the diffusion of valuable 8Ci- 



entijic knowledge, in a readable and attractive form, among all classes 



of the commimiti/, and has thus far met a want supplied by 



no other magazine in the United States. 



Ten volumes liave now appeared, -which are filled -nith instructive and interesting 

 articles and abstracts of articles, original, selected, translated, and illustrated, from the 

 pens of the leading scientific men of different countries. Accounts of important scien- 

 tific discoveries, the application of science to the practical arts, and the latest views put 

 forth concerning natural phenomena, have been given by savants of the highest au- 

 thority. Prominent attention has been also devoted to those various sciences which 

 help to a better understanding of the nature of man, to the bearings of science upon 

 the questions of society and government, to scientific education, and to the conflicts 

 which spring from the progressive nature of scientific knowledge. 



The PoptTLAB SciEXOE Monthly has long since ceased to be an experiment. It 

 has passed into a circulation far beyond the most sanguine hopes at first entertained, 

 and the cordial and intelligent approval which it has everywhere met shows that its 

 close and instructive discussions have been well appreciated by the reading portion of 

 the American people. It has not been its policy to make boastful promises of great 

 thin^ to be done in the future, but rather to appeal to what it has already accom- 

 phshed as giving it a claim upon popular patronage. But no pains will be spared to 

 improve it and make it still more worthy of liberal support, and still more a necessity 

 to the cultivated classes of the coimtry. 



The Populae Science Monthly is published in a large octavo, handsomely printed 

 on clear type, and, when the subjects admit, fully illustrated. Each number contains 

 12S pages. 



Terms : $5 per Anmiin, or Fifty Cents per Number. 



Postage free to all Subscribers in the United. States. 



A new volume of The Poptjlak Science Monthly begins with the numbers for 

 May and November each year. Subscriptions may commence fi"om any date. Back 

 numbers supplied. 



Kow Ready, Vols. /., //., ///., IV., V, VI., VII., VIII., IX., and X., of The 

 Popular Science Monthly, embracing the numbers from 1 to 60 (May, 1S72, to April, 

 1877). 10 vols., 8vo. Cloth, $3.50 per vol. Half Morocco, $6.50 per vol. 



For Sale, Binding Cases for Vols. /., //., ///., IV., V, VI., VII., VIII., IX., 

 and X.. of The Popular Science Monthly. These covers are prepared expressly- 

 for binding the volumes of Tue Populae Science Monthly as they appear, and will 

 be sent to Subscribers on receipt of price. Any binder can attach the covers at a tri- 

 fling expense. Price, 50 cents each. 



ADDEE38 D. APPLET ON &- CO., Publishers, 



&49 «fe 551 Beoadway, New Yoek. 



