140 METEOROLOGICAL OBSERVATIONS. {October, 



As Lieutenant Cheyne had brought with him sup- 

 plied, I understood, chiefly from Kew some very delicate 

 electrometers, I determined that he should have every 

 assistance the service admitted for attending to the influ- 

 ence which the aurora might exercise. To ensure this, he 

 was excused from other duties, and directed to attend 

 to the registry of thermometers ; and as it would be in- 

 convenient to send officers aloft to register thermometers, 

 I adapted a balance-pole of twenty-eight feet in length, so 

 that it could be easily pulled down ; to this a minimum 

 thermometer was attached, to be read at eight A.M., at 

 noon, and at four P.M. Another plain thermometer was 

 also fixed at twenty feet, and one of the standards was 

 placed on pikes at four feet above the earth, near the 

 Observatory, independent of the general board, contain- 

 ing fifteen standard thermometers from Kew and Green- 

 wich, under the boat. The pike-thermometer was regis- 

 tered hourly with the magnetometer. A very delicate 

 electrometer was also placed in the Observatory, but 

 was broken not many hours after by the prying curiosity 

 of some meddler. 



Before the 8th of October the general observations on 

 the magnetometer were supposed to commence; at all 

 events, the registry dates from noon of that day. The 

 officers who volunteered for that duty were Lieutenant 

 May, Mr. Herbert, Mr. Grove, Mr. Pym, mates, and 

 Messrs. Harwood and Webb, engineers, of the ' Pioneer.' 

 The observations were continued hourly, both night and 

 day, throughout the winter, up to July. Various other 

 observations were carried on by myself, at the instance 

 of Mr. Glaisher, of the Royal Observatory, Greenwich, 



