700 



SCIENCE. 



[N. S. VOL. VIII. No. 203; 



preliminary program, but were omitted from 

 the regular program because no abstracts 

 Tvere furnished. 



Erwin p. Smith, 



Secretary. 



SUBVEYS OF TSE GATEWAYS TO ALASKA. 



A BEGINNING has at last been made in 

 the accurate mapping of the delta of the 

 Yukon, one of the great rivers of the 

 world. Through the courtesy of Superin- 

 tendent Pritchett we are enabled to give a 

 preliminary account of the work done in 

 that locality during this year and to advert 

 to further operations of the Coast Survey at 

 the head of Lynn Canal, another of the 

 gateways to the interior of Alaska and the 

 British Yukon district. 



On June 30th the U. S. Coast and Geo- 

 detic Survey party arrived in St. Michael, 

 Alaska, and immediately began prepara- 

 tions for the survey of that part of the 

 delta of the Yukon River bordering on the 

 seacoast. 



The prime object of this expedition was 

 to examine the delta of the Yukon River 

 with the purpose of hnding out what depth 

 of water exists on the bars in front of the 

 delta and to locate such channels as were 

 found flowing from the mouths of the river 

 into Bering Sea. This problem necessitated 

 the execution of a scheme of triangulation 

 upon which to base the required topog- 

 raphy and hydrography. 



While the two small steamers required 

 for hydrographio work off the delta were 

 being fitted out by a section of the party at 

 St. Michael the other members were en- 

 gaged in triangulating and mapping the 

 coast from St. Michael southward to the 

 the Aphoon (pronounce Ap-hoon) mouth 

 of the Yukon, and in making a detailed 

 survey of the towns of St. Michael, Healy 

 and immediate vicinity. This detail map 

 proved of much value to the military au- 

 thorities of St. Michael Military Reserva- 



tion in settling the matter of boundary- 

 lines between the commercial companies lo- 

 cated there. 



The channel and bar of the Aphoon moutb 

 of the Yukon River were surveyed and de- 

 veloped. This is the channel that has al- 

 ways been used by steamboats for getting, 

 into the river from St. Michael. 



While this work at the Aphoon mouth 

 was in progress another small party had 

 gone on one of the small steamers to the 

 Kusilvak mouth of the river, establishing a 

 latitude and longitude station well inside of 

 the coast line. From this station it pro- 

 ceeded seaward with a topographic and 

 hydrographic survey. 



From all reports of the natives and others- 

 it seems reasonably certain that the Kusil- 

 vak mouth is the deepest of the mouths of 

 the river, and this survey shows that it has 

 much the greatest volume of water. 



From the latter part of August to the end' 

 of the season the whole party was at work 

 on the Kusilvak mouth of the river and: 

 southward along the coast, including and 

 beyond the mouth of the Krypniak River. 

 The Kusilvak mouth was found to be about 

 twenty-five miles farther northwest than 

 given on the most recent charts. All that 

 can now be said of this mouth of the river 

 is that eight feet of water can be carried 

 into it at low tide, whereas there is only 

 two feet at low tide on the bar at the en- 

 trance to the Aphoon mouth, the one now 

 used by steamboats plying on the Yukon- 

 River. 



From the investigations made of the 

 Kusilvak mouth the shallowest water on 

 the bar is from thi-ee to six miles off shore 

 and the eight-foot channel is very crooked 

 and difficult to follow with a vessel. It 

 cannot be followed at all except b}' the con- 

 stant use of a sounding lead. The use of 

 buoys appears impracticable on account of 

 the outflow of ice each year, which would 

 not only carry the buoys away, but no 



