tant channels into Delaware Bay, one of which is open when the 

 old channels are choked with ice, and is thus invaluable, in the 

 winter season, to our coasting trade; and of another on the coast of 

 the State of Mississippi, the Coast Survey has already detected and 

 published nine dangerous shoals in the vicinity of Nantucket, and 

 numerous rocks in Long Island Sound and its vicinity. If these 

 were the only practical benefits to be derived from it, they would 

 more than repay all its expenditure. Obstructions of a similar cha- 

 racter have been discovered in the Delaware and Chesapeake Bays, 

 and doubtless many more will reward its labours upon the coast fur- 

 ther southward. 



The information derived from the Coast Survey has also been 

 made useful in the determination of the proper sites for light-houses 

 along our coast, and in assisting the local surveys which the authori- 

 ties of the various seaboard towns desire to have made. And when, 

 in the progress of civilization, the citizens of our different States 

 shall feel the importance of following the excellent example set them 

 by Massachusetts, and substituting true topographical maps of their 

 territories for the fancy sketches which now bear that name, the re- 

 sults of the Coast Survey will be found of great utility to them in 

 establishing their bases and verifying their work. 



But, after all, the great practical utility of the work will be found 

 in the publication of cheap and trustworthy maps, which, while they 

 furnish valuable information to all, will be instrumental in diminish- 

 ing that fearful loss of lives and property which annually takes place 

 along our extensive and exposed coast. 



When we turn to inquire what benefits to science have arisen, or 

 are likely to arise, from the Coast Survey, under its present organi- 

 zation, their number and importance almost preclude an elaborate 

 reply. 



The first and most prominent point of scientific interest upon which 

 its results will be brought to bear, will, of course, be the determination 

 of the length of a degree of latitude, between different parallels, and 

 from this, of the figure of the earth. A problem considered of such 

 importance that surveys, more costly than that of our coast is likely 

 to be, have more than once been undertaken by European nations, 

 for the sole purpose of obtaining its solution. And France, with that 

 honourable zeal which has placed her first in all matters of physical 

 science, has sent parties of her ablest men to the most remote regions 

 of the earth, to execute these measurements. As our Survey, when 

 completed, will extend over about 20° of latitude, the opportunity of 



