42 C. Abbe—Nebule of Herschel’s Catulogue. 
Art. VI.—The very much extended Nebule of Sir John Herschel's 
General Catalogue; by CLEVELAND ABBE. 
[Read before the Philosophical Society of Washington, June 4, 1874.] 
In 1865 and 1867, I considered carefully the question of the 
apparent distribution of the nebule in space, basing my studies 
upon the General Catalogue of Sir John Herschel. Among other 
points that occupied my attention, I attempted, by separating 
their satellites ; among the nebule we may expect to find analo- 
gous planes, whose relations to each other and to those already 
known cannot but be highly instructive. As yet we have but 
