138 
F. M. CAMPBELL—ON INSTINCT. 
similarly developed. Let us picture to ourselves au animal leaving 
some place of protection which we will call its home, and fearful 
of its enemies. After proceeding a very short distance it glances 
wistfully homewards, and as it cautiously moves onwards, it is 
ever turning towards the shortest line of retreat, apparently fixing 
only the direction of its home point, and allowing all intermediate 
impressions of position to pass out of record. It is not too much 
to suppose that the animal, or its descendants, would soon acquire 
the practice of hearing in mind the direction in which to run 
in case of danger, and that in the course of generations this habit 
would he constantly exercised for other purposes than that of 
safety. How, if “ the sense of direction ” has been developed in 
this manner, animals would incline to take the “bee-line ” home, 
as is stated to be generally the case. If they occasionally retraced 
their steps, I should not consider their action as due to “a sense 
of direction,” hut to its loss, which led them to employ their 
powers of scent and of remembrance of landmarks observed in the 
outward journey. It is also manifest that my hypothesis gets rid 
of the difficulty of the animal estimating the distance which it has 
travelled, and obviates the necessity for a theory of “registration 
of turns and curves.” The animal needs hut to recognise perpetually 
at any given instant its position in relation to its home, whether 
it is “ turning ” or “curving,” or taking a straight course. This 
it could not do if conveyed in a vehicle with no means of observing 
either the rate at which it was carried, or the direction in which 
it moved. 
It is obvious that animals which travel far from home have from 
their nature and surroundings much better opportunity of develop¬ 
ing the faculty of direction than mankind possess. Their wants 
are fewer, and they are not diverted from their more simple 
purposes by the variety of objects that perpetually attract and 
draw off the attention of human beings. Every one must be 
conscious how much a habit of reasoning trenches upon the 
province of observation ; yet there are moments of mental 
abstraction, during which some external object is unconsciously 
chronicled, and is often afterwards recalled and applied. The 
semi-conscious recognition of the direction of a locality, which, 
as already stated, I detected in myself, is but a step to its uncon¬ 
scious recognition such as displayed by the prairie-hunters. 
"Whether or no animals exercise unconsciously this faculty, is a 
question that does not affect my hypothesis. 
It is to be regretted that the experiments made on animals as to 
their “ sense of direction” have been so few, and that they have 
not increased our knowledge of that faculty. Sir John Lubbock 
has indeed shown that ants are greatly aided in recognising the 
direction in which they are going by the direction in which the 
light is falling.* 4 But this alone cannot guide them home. If, 
for instance, an ant left its nest in the morning with the sun 
* 1 Journ. Linn. Soc.,’ Zool., vol. xv, p. 381. 
