xxvi OFFICIAL INSTRUCTIONS. 



future observations, and to increase the chance of the observations of 

 both being preserved. 



We have caused a great variety of vakiable instruments to be put on 

 board the ships under your orders, of wliich you will be furnished with 

 a list, and for the return of which you will be held responsible ; and 

 we liave also, at the recommendation of the President and Council of 

 the Koyal Society, ordered to be received on board the Fury the Rev. 

 Mr. Fisher, who is represented to us as a gentleman well skilled in 

 Astronomy, Mathematics, and various branches of knowledge, to assist 

 you in making such observations as may tend to the improvement 

 of Geography and Navigation, and the advancement of science in 

 general. 



Amongst other subjects of scientific inquiry, you 'snll particularly 

 direct your attention to the variation and inclination of the magnetic 

 needle, and the intensity of the magnetic force ; you will endeavour to 

 ascertain how far the needle may be affected by the atmospherical 

 electricity, and what effect may be produced on the electrometic and 

 magnetic needles on the appearance of the Aurora Boreahs. You wiU 

 keep a correct register of the temperature of the air, and of the sea at 

 the surface, and at different depths. You will cause frequent observa- 

 tions to be made for ascertaining the refraction, and what effect may 

 be produced by observing an object, either celestial or terrestrial, over 

 a field of ice, as compared with objects observed over a sm'face of 

 water : together with such other meteorological remarks as you may 

 have opportunities of making. You are also to attend particu- 

 larfy to the height, direction, and strength of the tides, and to the set 

 and velocity of the currents ; the depth and soundings of the sea, and 

 the nature of the bottom, for which purpose you are suppHed with an 



