COIMTENTS. 



Article I. Bulletin of the Philosophical Society of 

 Washington. Vol. J, March, 1871, to June, 

 1874. Pp. 218. 



Article II. Bulletin of the Philosophical Society of 

 Washington. Vol. II, October 10, 1874, to 

 November 2, 1878. Pp. 452. 



Article III. Bulletin of the Philosophical Society of 

 Washington. Vol. Ill, November 9, 1878, to 

 June 19, 1880. Pp. 169. 



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