Scientific American, Vol. XXXIX.—No. 24. [New Series.], December 14, 1878 :  A Weekly Journal Of Practical Information, Art, Science, Mechanics, Chemistry, And Manufactures  [electronic resource] / 
Various 
 -  Project Gutenberg,  2012 
 - Project Gutenberg  38480 .
<br/><br/> Public domain in the USA. 
<br/><br/>Electronic text