

ANIMALS' ILLUSIONS 161 



often seem victims to illusions largely developed by the 

 imagination. The horse, for instance, is one of the 

 bravest of animals when face to face with dangers which 

 it can understand, such as the charge of an elephant, or 

 a wild boar at bay. Yet the courageous and devoted 

 horse, so steadfast against the dangers he knows, is a 

 prey to a hundred terrors of the imagination due to 

 illusions mainly those of sight, for shying, the minor 

 effect of these illusions, and ' bolting,' in which panic 

 gains complete possession of his soul, are caused as a 

 rule by mistakes as to what the horse sees, and not by 

 misinterpretation of what he hears. It is noticed, for 

 instance, that many horses which shy usually start away 

 from objects on one side more frequently than from 

 objects on the other. This is probably due to defects 

 in the vision of one or other eye. In nearly all cases of 

 shying the horse takes fright at some unfamiliar object, 

 though this is commonly quite harmless, such as a 

 wheelbarrow upside down, a freshly felled log, or a 

 piece of paper rolling before the wind. This instantly 

 becomes an * illusion/ is interpreted as something else, 

 and it is a curious question in equine neuropathy to 

 know what it is that the horse figures these harmless 

 objects to be. One conclusion is certain : all horses 

 share the feeling, omne ignotum pro mirabili^ with a 

 strong tendency to convert mirabili into terribili, and 

 night or twilight predisposes them to this nervous 



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