iso Lieut . Foster’s observations on the diurnal changes 
serve to mark with more precision than heretofore, all the 
circumstances of this daily change. On trial, the amount 
was found to be very considerably increased ; and he, still in 
pursuit of the same object, now undertook to ascertain the 
direction which the daily variation impressed upon the needle, 
when balanced at different azimuths ; which was easily done 
by a slight adjustment of the magnets ; and in this way he 
found that in two positions of the needle, viz. when its 
north end was directed either to N 16 0 W, or S 16 0 E, no 
daily variation, or a very little took place, and that on one 
side of this line, the needle passed in one direction, and on 
the other side in an opposite one. 
In the memoir which the Author published relative to 
these experiments, he expresses a wish that some other 
persons would pursue this enquiry ; and as the parts in 
which we were likely to winter in the recent voyage of dis- 
covery under Captain Parry, seemed highly favourable for 
the purpose, I determined to avail myself of this circum- 
stance, and to make a regular set of such observations. 
With respect to the daily variation, it was soon found, as 
was expected, that the needle being nearly neutralized by 
the great amount of dip, no artificial means would be neces- 
sary for increasing its amount : all the observations, there- 
fore, on this head, were made with the needles suspended in 
their natural state, and the following are entirely devoted to 
the second object, viz. of determining the direction which 
the needle takes in consequence of the daily variation when 
directed to different points of the compass, and to ascertain 
the line of no daily variation, or at least that line in which 
the motion is a minimum. 
