DESCRIPTIONS OF STATIONS. 



As stated in the previous volume, one of the chief difficulties experienced by the 

 observers of the Department of Terrestrial Magnetism in the reoccupation of old 

 stations for secular-variation data has been the lack of necessary information to 

 permit precise recovery of the point where the previous observations were made. 

 Ouing to the frequent occurrence of local disturbances, it may readily happen that 

 erroneous secular-variation data will result from non-recovery of exact station. 

 Accordingly the observers of the Department are instructed to furnish as complete 

 descriptions as possible of stations occupied, especially of such as give promise of 

 future availability. Information additional to that contained in the published 

 descriptions or copies of station-sketches or of photographs of surroundings will 

 gladly be furnished those who are interested in the reoccupation of any of the 

 stations. 



The descriptions are given in alphabetical order under the same geographical 

 divisions adopted in the Table of Results. The general form followed in the 

 descriptions is: Name of station, year when occupied, general location, detailed 

 location, distances and references to surrounding objects, manner of marking, and 

 finally the true bearings of prominent objects likely to be of permanent character. 

 All bearings, unless specifically stated otherwise, are true ones, and are reckoned 

 continuously from to 360, in the direction, south, west, north, east. Occasionally 

 no description of a station listed in the Table of Results will be found; this is because 

 the description as furnished by the observer, for one reason or another, was too mea- 

 ger to be worth publishing. For some expeditions, owing to the absence of surround- 

 ing objects to which reference could be made, the descriptions of stations naturally 

 could not be made very full or precise. When no mention is made of marking of 

 station, it is to be understood that the station was either not marked at all or not in 

 a permanent manner. 



The majority of the measured distances were made originally in the English 

 system; however, the distances obtained by conversion into the metric system are 

 also given, but inclosed in parentheses, so as to show that they are converted figures. 

 The following rules have been adopted in the conversions: distances given to 0.01 

 foot are converted to the nearest 0.001 meter, 0.1 foot to the nearest 0.01 meter, 

 1 foot to the nearest 0.1 meter, estimated feet or yards to nearest meter, estimated 

 fraction of a mile to nearest 0.1 kilometer, estimations of more than a mile to nearest 

 kilometer. Short and important reference distances, when measured accurately, 

 have been converted into nearest 0.1 centimeter; such measurements, however, as, 

 for example, dimensions of marking-stones, etc., which are not of great importance, 

 have been converted to the nearest centimeter. If a distance is given immediately 

 preceding an azimuth of a mark, it is to be interpreted as distance from the mag- 

 netic station to the mark. 



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