[CORRECTION.] 
Washington, September 15 th, 1846. 
Francis Markoe, Jr., Esq., 
Corresponding Secretary of the National Institute. 
Dear Sir : In the third Bulletin of the National Institute, containing the pro- 
ceedings of the meeting of April, 1844, the following announcement appears at 
page 432 : 
“ On the measurement of Base Lines — Captain W. A. Swift, U. S. Army." 
Supposing that the paper thus designated was intended to represent the title of 
the paper which I had the honor to read before the society on the 5th April, 1844, 
I beg to state, that the words used in the announcement quoted above, convey 
neither the idea of the character of the paper in question, nor the object which I 
had in view in making it. 
The title, as prefixed by myself, is as follows : 
“ Description of the Base of Long Island, ( New York ,) measured by Ferdinand 
R. Hassler, Esq., in the year 1834, for the survey of the coast of the United 
States.” 
I have to request the favor of you to cause the error which I have pointed out 
in the title to be stated in the forthcoming bulletin of the society’s proceedings, in 
order that the purport of the paper may not be misunderstood. It does not profess 
to be upon the “ Measurement of Base Lines on the contrary, it assumes to be a 
description of the Base of Long Island, in the operations of which it became my 
duty, as one of Mr. Hassler’s assistants in the coast survey, to partake, from the 
commencement to the termination thereof. 
Very respectfully, your obedient servant, 
WM. H. SWIFT, . 
Capt. Topog. Engineers. 
