112 



Ocean Magnetic Observations, 1905-16 



NORTH AMERICA. 



United States — continued. 



part of the lawn in front of the officers' quarters; 

 marked by small hole in top of a rough stone 6 by 6 

 by 12 inches (15 by 15 by 30 cm.) with a flat top which 

 projects sUghtly above the general surface. In 1908 

 three secondary stations were estabUshed. The first 

 is 74 feet (22.6 meters) true north 56° 08' east of main 

 station. The second and third, used for ship instru- 

 ments, were about 45 feet (14 meters) west of and 

 35 feet (11 meters) northwest of main station, re- 

 spectively. [Main station reoccupied in 1910.) 

 Kulkan Island, Alaska, 1907.— On the eastern point of 

 land on Kutkan Island, 30 feet (9 meters) from the 

 water's edge, at high tide, on the north side, 12 feet 

 (4 meters) on the south side, and 50 feet (15 meters) 

 from extreme eastern edge of island. A cross, cut 

 in the top of a large irregular rock projecting about a 

 foot above ground, marks the exact spot. The fol- 

 lowing true bearings were determined ; pier at Sitka 

 absolute magnetic observatory, 156° 49^3; U. S. 

 Marine Corps barracks flagstaff, 148° 5112; Mission 

 flagstaff, 187° 33:1. 

 San Dugo, California, 1905, 1906.— Five stations were 

 established here; these are designated as San Diego /, 

 Secondary, II, III, and C. & G. S., 1897. 



The first, San Diego /, is near the northern pomt 

 of North Coronado Beach Island; near the shore of 

 the bay, facing the city, about 320 paces west of the 

 west corner of engine house of Marine Railway 

 (Spreckels) and 58 paces from road that rune along the 

 beach. Beacon No. 10 bears approximately north- 

 northwest from the station, which is marked by a 

 spruce post, 6 by 6 by 50 inches (15 by 15 by 127 cm.) 

 set with its faces approximately with the cardinal 

 points and projecting about 1 foot (30 cm.) above the 

 surface; the letters C. I. are cut on the north face and 

 1905 on the south face. The foUowuig true bearings 

 were determined: School of Theosophy, 96° 4718; 

 stand pipe, 187° 54!2; flagpole on south tower of 

 Coronado Hotel, 338° 38:4. A secondary station, 

 designated as .Sp(-o?i(iary, was established 50 feet (15.2 

 meters) south-southeastward in the line toward the 

 Coronado Hotel from San Diego I. ^ 



San Diego // is on the northwest portion of North 

 Coronado Beach Island, about midway between the 

 C. & G. S. station at Quarantine and Station I; 

 about 75 yards (69 meters) from the northwest beach 

 of North Coronado Beach Island, and in the line 

 joining Harbor Beacon No. 2 and the south end of 

 the most southerly building on Quarantine WTiarf; 

 marked by a redwood post 4 by 6 by 44 inches (10 by 

 15 by 112 cm.) projecting about 8 inches (20 cm.) 

 above ground. The letters C.I. and the numeral II 

 are cut on the two faces which face the north and 

 south respectively. The following true bearings were 

 determined : south tower of Coronado Hotel, 306° 40 ! 8 ; 

 old lighthouse, Point Loma, 33° 37:7; central dome, 

 Schoolof Theosophy, 117° 28: 1. 



San Diego /// is on the north shore of San Diego 

 Bay, on a low beach northwest of Dutch Flat, and 

 about 100 yards (91 meters) north 25° east of a 

 triangulation signal on the sand spit; marked by 

 redwood post 4 by 6 by 52 inches (10 by 15 by 132 

 cm.) extending about 10 inches (25 cm.) above 

 ground and having the letters C. I. cut in the north 

 face, and a hole near the center of the top. The 

 following true bearings were determined : south tower 

 of Coronado Hotel, 337° 19:7; old Ughthouse, Point 

 Loma, 24° 08:i; School of Theosophy, 63° 2811. 



The C. & G. S. 1897 station, occupied in 1905, is 

 that estabUshed by the Coast and Geodetic Survey 

 in 1897. It is in the northeast portion of the city, 

 about 150 feet (46 meters) southwest of where 

 Seventh and Fir streets would intersect if extended 



NORTH AMERICA. 



United States — concluded. 



into the park; marked by redwood post 4 by 4 by 36 

 inches (10 by 10 by 91 cm.) projecting about 1 foot 

 (0.3 meter) out of ground, lettered U. S. MAG. and 

 1897 on its north and west vertical faces respectively. 

 San Francisco, Presidio, California, 1905. — The station 

 of the U. S. Coast and Geodetic Survey of 1904, at 

 the triangulation station on Presidio Hill, northwest 

 of gate on south side of Presidio grounds at the edge 

 of the woods, was reoccupied; marked by stone post 

 6 inches (15 cm.) square on top, projecting 6 inches 

 (15 cm.) above ground and lettered on top U. S. C. 

 & G. Survey, 1881. The following true bearings have 

 been determined; cross on Lone Mountain, 325° 53:8; 

 center of top of Drake Cross, 27° 03 : 7. [This station 

 reported in 1916 as no longer suitable. A 6 million 

 gallon reservoir is now on the site.] 



San Rafael, California, 1905, 1908.— There are three 

 stations, two being those of the U. S. Coast and 

 Geodetic Survey of 1897. They are 1.1 miles (1.8 

 kilometers) northwe.stward from the county court- 

 house, on the eastern slope and near the top of a hill, 

 about 375 feet (115 meters) distant from one of the 

 water company's reservoirs. There is a meridian hne 

 marked by two marble posts 8 by 8 by 48 inches 

 (20 by 20 by 122 cm.) projecting about 24 inches 

 (61 cm.) above the surface of the ground; the north 

 stone is lettered U. S. C. & G. S. on its west vertical 

 face, MAG. STA. on the south face, and 1897 on the 

 east face, and bears a cross on its upper face marking 

 the exact point. The south stone is set about 2,300 

 feet (701 meters) true south of the station, its north 

 vertical face being lettered MER. MARK., the east 

 face U. S. C. & G. S., and the west face 1897. 



In 1897, 1905, and 1908, dip-circle observations 

 were made at a point, designated as Dip Station, 50 feet 

 (15 meters) from the north stone, and magnetometer 

 observations were made at a point, designated as 

 Magnetometer Station, 10 feet (3.0 meters) from the 

 north stone in the extension of the line from flagstaff 

 on the county courthouse to the north stone. In 

 1908 observations were also made over the north 

 pier The flagpole on county courthouse is in true 

 bearing 289° 46 :0. 



Sitka, Alaska, 1907.— Two stations occupied; the principal 

 pier in the Sitka auxiliary magnetic observatory of 

 U. S. Coast and Geodetic Survey, and in the regular 

 absolute house. 



SOUTH AMERICA. 



Pertt. 



San Lorenzo Island (Callao Harbor), Lima, 1908. — The 

 main station is about 5.5 feet (1.7 meters) above and 

 about 50 feet (15 meters) distant from the ordinary 

 high-water mark on the beach, and is approximately 

 the U. S. Coast and Geodetic Survey station of 

 1907. It is 79 feet (24.1 meters) and 67.4 feet 

 (20.54 meters) from the northeast and southeast 

 comers of the powder magazine (marked " Deposito 

 de explosives"), which are in true bearing north 68?7 

 west and south 34?1 west respectively, and 57.5 feet 

 (17.5 meters) from door of magazine directly beneath 

 flagstaff. The point is marked by a small round stake 

 driven flush with ground. The following true bear- 

 ings were determined: square tower with clock in 

 Callao, 250° 31 :0; spire of church on point in Callao, 

 256° 00:7. A secondary station designated as San 

 Lorenzo Island 2 was estabUshed at a point south 31° 

 east true 52.5 feet (16.0 meters) distant from main 

 station. 



