READY FOR THE PRESS. 



VOLUME FOUR OF THE NEOMONIC SERIES. 



THE LIFE OF BOLYAI. 



From Hungarian (Magyar) sources, by Dr. George Bruce 

 Halsted. [Containing the Autobiography of Bolyai Farkas, now 

 first translated from the Magyar.] 



VOLUME FIVE OF THE NEOMONIC SERIES. 



NEW ELEMENTS OF GEOMETRY 



WITH A COMPLETE THEORY OF PARALLELS. 

 BY N. I. LOBACHEVSKI. 



Translated from the Russian by 

 DR. GEORGE BRUCE HALSTED. 



[Though this is Lobachevski's greatest work, it has never be- 

 fore been translated out of the Russian into any other language 

 whatever.] 



