348 Mr. Harvey's experimental inquiries relative to the 
meridian, it is well known that the intensity of each point 
will diminish, as the stations are brought into a position at 
right angles with the first ; and on the contrary, an increase 
of intensity will be observed when they are removed from 
the latter situation to the former. Changes of a similar kind 
may be distinctly traced in all the preceding observations. 
At either stations, e" and U', for example, an increase of inten- 
sity was perceived as the ship moved from the position when 
her head was easterly, to that when it bore due north ; and 
a similar change was observed at v" and h!" , as her bow 
passed from a westerly direction to one exactly south. So 
also at the station H'", an augmentation of intensity was 
remarked as her head moved from a westerly to a southerly 
position ; and on the contrary, a diminution of intensity as 
the direction of her bow was changed from south to west. 
In like manner at the station a!' , an increase of the mag- 
netic power was discovered as the vessel passed from east to 
north ; but a diminution of intensity as she moved from 
north to east. At the stations vi " , H", L", E /tf , and K!", a de- 
crease of intensity was likewise apparent as her head was 
carried by the current from south to west ; and a change of 
a similar kind as it varied from north to east. 
From these considerations it appears, that the changes in 
the magnetic intensity, at any station in the vessel, are regu- 
lated by laws analogous to those which influence simple 
masses of iron. 
The variations of intensity however at the several stations 
were of a very unequal kind. In some parts of the ship, the 
alteration of a quarter of a point in the direction of her head 
was productive of a greater change than the variation of an 
entire point at some other stations. Nor does the change of 
