58 



the most delicate nature, since any error, committed in this early part 

 of the work, will necessarily be multiplied throughout the series of 

 triangulations which rest upon it. The bases of verification re- 

 quire to be measured with the same degree of accuracy, as otherwise 

 they could not serve as a check upon the calculated results. Nor is 

 less precision necessary in the measurement of the angles of the pri- 

 mary and secondary triangulations, which serve as checks upon each 

 other, since the position of any point in the former is determined by 

 each of these series. And, again, at every important point the astro- 

 nomical observations for latitude and longitude again control the 

 results of the geodetic operations. In this way, although absolute 

 accuracy can never be expected from human work, and especially 

 from that which requires so many observations and calculations for 

 its elaboration ; yet the possible error is reduced to so small a quan- 

 tity, that it may be, for all purposes of commerce and internal im- 

 provement, neglected. But to obtain these results the whole resources 

 of science are requisite; and it is necessary that he to whom such a 

 survey is entrusted, should have a thorough familiarity with what 

 has heretofore been done in this regard by other nations, and should 

 possess, besides, that degree of talent and profound science which 

 will enable him to judge of the results of the eminent men who have 

 preceded him, to select what is worthy of imitation in their processes, 

 and improve upon that which is defective. 



When, however, a survey of this kind is conducted with the requi- 

 site degree of precision, its results become incalculably useful, not 

 only in a pecuniary point of view, to the government and citizens, 

 but to the advancement of science, and, through it, of civilization and 

 the general welfare of mankind; and there are, in many branches of 

 science, problems not yet definitely solved, to the correct elucidation 

 of which the observatiDns of the Coast Survey will become available. 

 Hence the cause of science, not less than that of self-interest and 

 humanity, is involved in the proper conduct of such a survey; and, 

 by its promotion, while we improve our commerce and relieve our 

 seamen from a portion of the dangers to which they are exposed, we 

 shall raise our national character, and justify our position among the 

 great nations of the earth. 



If, now, we attempt to compare our Coast Survey with similar 

 works executed abroad, we shall find just cause of pride in the man- 

 ner in which it has been conducted. 



The regulation introduced by the present Superintendent, by which 

 the field-work, at first computed by the party making it, is after- 



