248. Coast Survey of the United States. 
the British rule were adopted, of putting the buoys of one color 
on one side of the channel, and»those of another on the other 
side, and numbering them in order from out, inwards, then the 
mariner in the night, or a fog, falling in with one of them, would 
know the precise spot he was in, and the course to be steered to 
the next buoy. Further details could be added concerning their 
moorings, as for example, the propriety of using the screw pile, 
introduced into this country by Capt. Wm. H. Smith of the To- 
pographical Engineers, but the preceding hasty remarks show 
the importance of the subject, and its present state of neglect. 
| Since the coast survey has been under its present head, five 
sheets of charts have been issued ; four of them are sheets of the 
large chart of New York bay, and were two-thirds done under 
Mr. Hassler. ‘Two more are wanting to complete this set. They 
will contain the south side of Long Island, and the east entrance 
of the Sound, and may appear before this paper is published. 
The small chart of New York bay and harbor has been for sale for 
some time in the principal cities, and begins already to be in 
demand. The charts of Delaware Bay, of the coast of New 
York, and of Long Island Sound, are in the engraver’s hands and. 
advancing rapidly. In order to expedite the publication, and em- 
ploy the skill and talent of other engravers, maps of the smaller 
harbors will be executed out of the office. 'The maps of Fisher’s 
Island of the old work, of New Bedford and Annapolis, with the 
Severn of last year’s work, are in progress. This isa part of the 
system of getting out results as soon as possible. The last men- 
tioned will be engraved in a less elegant style of finish, being 
subject to future improvement, especially in their astronomical 
determinations. : 
But this subject, however interesting, must be brought to a 
close. It was said at the beginning of this article, that the chief 
aim of it was to convey some idea of the methods and principles 
of observation and reduction introduced into the work by Dr. 
Bache himself, and to show that this noble undertaking has lost 
no ground during the past eighteen months of its existence. 
_ Even more than this could be justly maintained, were it not 
above all things, desirable to avoid unseasonable and unprofitable 
comparisons. 
As the duties of the survey are numerous, various, and com- 
prehensive, so the labor of arranging them, of adjusting each to 
