214 



Land Magnetic Observations, 1914-20 



78 days of actual field work, giving an average of 6^ days per station. The total travel, 

 including the return to Washington, amounted to 5,150 miles, of which 940 miles were 

 field travel, making an average of about 78 miles field travel per station. 



The stations occupied during this trip, with dates and geographic positions, were as 

 listed in Table 37 below; for magnetic data, see Table of Results. 



Table 37. 



No. 



3 



4 



5 



6 



7 



8 



9 



10 



11 



12 



13 



Name ' 



Lima 



Oroya 



Cerro de Pasco .... 

 Huanuco, A, B. . . . 

 Hacienda San Juan 



Tingo Maria 



Hacienda Putante . 



Shiraca 



Huacrachuco 



Andomayo 



La Limefia 



Chimbote 



Lima 



Date 



1917 

 May 1,7 

 " 18 



June 



July 



Aug. 



21 

 26-30 



7 

 13-14 

 2122 



5-6 

 11 



19-20 

 22 

 24 



8-9 



Lat. South 



12 

 11 

 10 

 9 

 9 

 9 

 8 

 8 

 8 



9 

 12 



04.3 

 32.6 

 41.3 

 56.1 

 31.2 

 17.1 

 24.2 

 39.0 

 36.2 

 38.6 

 40.5 

 04.1 

 04.3 



Long. East 



282 58 

 284 05 



283 45 

 2S3 45 



284 08 

 284 07 

 283 53 

 283 37 

 283 07 

 282 22 

 281 56 



281 25 



282 58 



All the stations are in Peru. 



The results obtained do not indicate any unusual local magnetic disturbances despite 

 the fact that at almost every station occupied the sand or loam contained particles of 

 of iron ore which could be separated by the use of a magnet, such iron being particularly 

 plentiful along the western coast. At the higher altitudes, the observing tent collected 

 high static charges so that discharges would occur whenever the observers got close to 

 the tent. 



The officials of Peru were very courteous and did everything possible to facilitate 

 the work of the expedition. As on various former occasions, the official through whom all 

 negotiations were conducted was Sehor G. Cisneros y Raygada, Introductor de Ministros, 

 whose active assistance and interest were much appreciated. The hospitality accorded 

 by all the haciendas and chacras within the Montana was very cordial. I wish par- 

 ticularly to mention Sehor Trujillo of Hacienda San Juan and Sehor Aguilo of Uchiza. 



Synopses of Additional Magnetic Surveys, 1914 to 1920. 



Besides the expeditions for making magnetic observations which are briefly described 

 in the foregoing reports, the following work has been done in the period 1914 to 1920: 



Roald Amundsen. Cooperative arrangements were entered into between the Depart- 

 ment of Terrestrial Magnetism and Captain Roald Amundsen, leader of the "Maud 

 Expedition" to the Arctic: Captain Amundsen offered to furnish copies of all magnetic 

 observations made on the expedition; the Department provided the necessary magnetic 

 instruments for Arctic work (see p. 8 and PI. 2) and program of observational work, 

 and it engaged to make the reductions of the observations as required. Magnet- 

 ometer No. 8 and dip circle No. 205 were the instruments furnished, together with the 

 usual accessories and additional equipment demanded by the nature of the contemplated 

 work. The expedition left Christiania, Norway, in July 1918, and spent the following 

 winter at a point called Maud Haven on the Siberian coast in east longitude 105 40'. 

 Here a temporary observatory was constructed of logs and driftwood, and provided with 

 2 piers on which observations were made during the stay at that place. Short inland 

 trips were made on which some magnetic work was done during April and May 1919. 

 The winter of 1919-1920 was spent at winter quarters on the coast in east longitude 



