MEASUREMENTS OF NEW BOGOSLOF 309 



bar or spit called ' the isthmus,' which at its narrowest 

 part was 326 feet wide. This is shown in Cantwell's chart 

 (fig. 16) and in Lieutenant Doty's photographs (fig. 17 

 and plate opposite this page). From this spit, and near the 

 base of the new volcano, rose a tower-like rock 87 feet 

 high with a slight inclination to the north Ship Rock 

 (see photogravure). Barnacles and watermarks were 

 found on the Rock twenty feet or more above sea level, 

 conclusive evidence of recent elevation. 



The general trend of the islands (or island, for at that 

 time the two were connected by continuous land) was 

 SE by E and NW by w. 



The position of Ship Rock, from observations made by 

 Lieut. J. W. Howison, was found to be: Lat. 5355 / i8"; 

 Long. i68oo'22" west. 1 



Heights and distances were determined by Lieut. D. 

 W. Hall by means of angular measurements. They are 

 herewith appended: 



Feet. 



Height of east pinnacle of Old Bogoslof ........ 334 



Height of center pinnacle of Old Bogoslof ...... 289* 



Height of west pinnacle of Old Bogoslof ........ 324 



Breadth of base of Old Bogoslof. .............. 933 



Height of Ship Rock ........................ 87.5 



Width of isthmus (narrowest) ................. 326 



Length of southern spit ...................... 1 ,824 



Extreme length of island ..................... 7,904 



Height of southeast peak of New Bogoslof. ...... 403 



Height of southwest peak of New Bogoslof ...... 475-500 



The length of the connecting spit is not definitely given, 

 but Cantwell states that on leaving the new volcano a 



1 The position of Ship Rock given by Stoney is : Lat. 5355 / 5 6 -3 // 5 Long. 



The position of new Bogoslof given by Tanner is Lat. 5354 / - 



2 This is obviously an error, as the photographs show that the middle peak 



was the highest part of the island (fig. 5). The 289 may be a typographical 



error for 389. 



