July 10, 1903.] 



SCIENCE. 



35 



Sea. This large river has its head waters 

 at the base of ^It. JleKinley, the highest 

 mountain on our continent, and among 

 Alaskan rivers is second only to the mighty 

 Yukon, whose desolate delta the survey has 

 already charted. No matter how inhos- 

 pitalile the shores, how rugged and for- 

 bidding, they will not challenge in vain the 

 skill and daring of our surveyors, as was 

 foretold by Charles Sumner in his speech 

 in favor of the aecjuisition of Alaska, in 

 which he alluded to the Coast Survey as 

 follows: "An object of immediate practical 

 interest will be the survey of the extended 

 and indented coast by our officers, bringing 

 it all within the domain of science, and 

 assuring to navigation much needed assist- 

 ance, while the republic is honored by a 

 continuation of national charts, where exe- 

 cution vies with science and the art of en- 

 graving is the beautiful handmaid." 



The Aleutian Islands, with their tower- 

 ing volcanoes and rugged and bold coasts, 

 stretch westward for twelve hundred miles 

 from the Alaskan peninsula and need yet 

 to be accurately charted. This chain of 

 islands lies along the shortest route from 

 Puget Sound to the Philippines, a route 

 which has already been followed by a ship 

 of the sui'vey in transferring its activities 

 from the sub-arctic waters of Bering Sea 

 to the tropical waters of the Philippines. 



In this new domain the survey has an- 

 other extensive field of operations. For in 

 general the surveys which were made prior 

 to the coming of the Americans are lacking 

 in accuracy and reliability, and are not at 

 all suited to meet the wants of an active 

 commerce. The Philippine archipelago 

 stretches northward from about latitude 

 5° to 21° and through about ten degrees 

 of longitude, and the intricate shore line 

 of its islands surpasses in length that of 

 the Tiiited States proper. Our Samoan 

 isljiiid po.ssessions and Guam remain to be 



surveyed, but in the Hawaiian Islands the 

 most needful work has been accomplished. 

 The size of the Philippines will be better 

 understood by comparison with an island 

 with which we are reasonably familiar. 

 Five islands in the Philippines are as large 

 or larger than Porto Rico, and two of these 

 each about ten times as large. 



To Porto Rico the survey promptly ex- 

 tended its work, for, almost before the 

 smoke of battle had cleared away, Admiral 

 Sampson called for accurate surveys of the 

 coasts of Porto Rico in a telegram ad- 

 dressed to the Secretary of the Navy, who 

 requested the survey to begin the charting 

 of its coasts. The work Avas at once in- 

 augurated, with surprising results. Hai-- 

 bors which had been unknown to the car- 

 tographer were discovered, surveyed and 

 mapped. A triangulation was extended 

 around the island and as far eastward as 

 the Danish island of St. Thomas, across 

 the Virgin Passage, famous as the prin- 

 cipal entrance into the Caribbean Sea, and 

 near which lies the winter rendezvous of 

 our na%y. All the principal harbors have 

 been charted and the results given to the 

 world. One of the interesting results of 

 these surve.vs is that cartographieally the 

 northern shore of the island was moved 

 southward half a mile and the southern 

 shore northward by the same amount. The 

 cause of this is that the visible i.sland of 

 Porto Rico is really the summit of a moun- 

 tain who.se slopes extend to great depths 

 below the adjacent seas. The results of 

 observations for latitude made on the north 

 and south sides of this summit are affected 

 by local attractions of mountain masses 

 which cause deflections of the plumb line 

 and which juust be taken into account in 

 charting the island. 



ITS GEOnETIC FrNCTION. 



When the inauguration of the survey was 

 under discussion at the beginning of the 



