Early Geographers of the United States 397 



and published the first American volume 

 of astronomical observations, was also a 

 large contributor to our geographical 

 literature. 



While he was director of the Astro- 

 nomical Expedition to Chile in 1853, he 

 was industriously engaged in collect- 

 ing data touching the geography and 

 statistics of that interesting country. 

 One of his associates, Lieutenant Mc- 

 Rae, U. S. N., returned to the United 

 States by crossing the pampas to Buenos 

 Ayres, procuring matter of great inter- 

 est for his report of the trip, and later 

 he returned to make further investiga- 

 tions regarding the interesting section 

 through which he passed. 



By their combined efforts the com- 

 mon geographical treasury of the world 

 was largely augmented. 



EXPLORATION AND SURVEY OF THE 

 PANAMA ISTHMUS 



Many attempts were made to fathom 

 the almost ' ' terra incognita ' ' of the 

 Panama Isthmus before the middle of 

 the 19th century without more than 

 negative results being produced ; but 

 the growing importance of the com- 

 merce of the United States created a 

 strong pressure on the part of the Amer- 

 ican people to seek to break the barrier 

 separating the two oceans which bound 

 this country. 



The people then naturally selected 

 the Navy of the United States, whose 

 main duty in peace times is to carry the 

 flag into distant countries, to explore 

 the Isthmus of Panama, and willing 

 leaders were found to attempt to make 

 a passage through the almost impene- 

 trable forests of that wild country. 



The first requisite of a canal which 

 would carry our ships from ocean to 

 ocean necessitated not only a crossing, 

 but the lowest crossing that could be 

 found, and as the axiomatic statement 

 that ' ' the bed of a stream or river fur- 

 nishes the line of lowest levels in the 

 basin drained ' ' was early propounded 

 as the basis for the exploration, the 



wisdom of the selection of the ' ' hydrog- 

 raphers ' ' of the country to do the work 

 was self-evident. 



It might be said that the commander- 

 in-chief of all the expeditions which 

 operated on the Isthmus was Rear Ad- 

 miral Daniel Ammen, U. S. N. In the 

 very beginning of the systematic inves- 

 tigation of the problem to which now 

 has been found an answer he took great 

 interest, and early and late hammered at 

 the problem until the day of his death. 

 Balked in his desires to personally lead a 

 party in the field, using the commanding 

 influence of his great friend, President 

 Grant, who had called him to Washing- 

 ton mainly because of his extensive 

 knowledge of this subject, he was in- 

 strumental in fitting out several expe- 

 ditions to survey routes for the canal. 



I need not go into the numerous de- 

 tails of the surveys made on the Isthmus 

 of Panama by American naval officers 

 to show how much the final project to 

 join the Atlantic and the Pacific Oceans 

 owes to them for its present promising 

 condition, and indeed I must content 

 myself with barely mentioning some of 

 the names of the gallant officers engaged 

 in this important undertaking, begin- 

 ning with the attempt at exploration 

 by Lieutenant Strain, U. S. N., in 

 1844. This expedition was unfortu- 

 nate as far as its personnel was con- 

 cerned, but nevertheless the information 

 acquired was of great utility, negative 

 though it may have been ; for it has 

 been only by a process of elimination 

 that a final conclusion was reached as 

 to relative advantages of the many 

 routes presented to geographers for dis- 

 cussion. Strain proved that the Darien 

 route was impracticable, and notwith- 

 standing the mishaps of the part}' the 

 results obtained created such emulation 

 among his brother officers that they 

 never let the matter drop until the final 

 plans for building the ' ' World's Canal ' ' 

 were completed. 



The name of Lieut. T. A. M. Cra- 

 ven might also be mentioned in connec- 



