OF THE UNITED STATES. ;343 



cd for accuracy, as well as approacliino; nearest to the fi2;urc 

 ot the coast, anil to lind a i)ro|)er place for a l)asc line to 

 ground them upon. 



In this operation, I should wish to be accompanied by a 

 man acquainted with tlic part of the country I shall have to 

 go thiougli, and to he allowed an expenditure, for tlie trans- 

 portation olthc small instruments, the erection of temporary 

 signals, ^'c. 



'I'hus prepared, it would i)e possible to make the actual 

 measurement of one base line in the latter jiart of the sum- 

 mer or in the fall of the present year. Dining this time, the 

 building of at least one of the ol)servatories should be com- 

 j)leied. The instruments destined for it could then I)e put 

 up during the winter, and the adjustment of those intended 

 for the survey itself could be made with the necessary at- 

 tention and minuteness. 



The work of the principal survey will he to form a chain 

 of tiiangles, with sides of about thirty miles in lengtli, along 

 the whole extent of the coast, so as to join the distant parts 

 by the shortest and most accurate lines possible, and to de- 

 termine the azimutlis of the sides of the triangles, and the 

 latitudes and longitudes of their angular points. 



Within these, a series of triangles, with sides of about ten 

 miles, will be formed to join them, part of which it will some- 

 times be possible to carry on simultaneously with the large 

 ones. The object of these will be to furnish an ample num- 

 ber of determined points, to which the survey may be re- 

 ferred, in all its details. 



It will be necessary to furnish the chief operator with the 

 following assistance : 



1. Two officers of the corps of engineers, well informed 

 in mathematics, and with so much knowledge of the practi- 

 cal operations, as will enable them to make the secondary 

 observations, and to keep the journal of them correctly. 



2. Twelve men of the corps of engineers, most of them 

 artificers, with a sergeant and corporal. 



