Causality—­i.e., the gift of tracing a recondite connection of cause and effect—­is another faculty which many varieties of monkeys possess in a decidedly ultra-instinctive degree.  I remember the surprise of a picnic-party who had borrowed my young Rhesus and on their return tied him up on the porch of a garden-house.  During the trip the little scamp had behaved with the decorum of a well-bred youth, but, finding himself unobserved, he at once made a vicious attempt to tear his rope with his teeth.  Whenever his boon companions approached the porch he would resume his attitude of innocence, but as soon as they turned away, which they often did on purpose to try him, he promptly recommenced his work of destruction.  Their giggling, however, excited his suspicions, and, seeing them peep around the corner, he suddenly became a model of virtuous inactivity.  One of the picnickers then entered the garden-house by a rear door, to watch the little hypocrite through a crack in the board wall, while his companions ostensibly walked away and out of sight.  As soon as everything was quiet.  Master Rhesus went to work again, but at the same time kept his eye on the corner till he was interrupted by a tap on the wall and a mysterious voice from within, “Stop that, Tommy!” Tommy started, peeped around the corner, and looked puzzled.  He was sure there was nobody in sight.  How could an invisible spy have witnessed his transgression?  He then scrutinized the wall more closely, discovered the crack, and dropped the rope with a curious grin, as he squinted through the tell-tale aperture.  He had traced the effect to its cause.

Unlike dogs, raccoons, or squirrels, chained monkeys rarely entangle themselves:  they at once notice the shortening of their tether, and never rest till they have discovered the clue of the phenomenon.  A dog in the same predicament has to content himself with tugging at his chain or gnawing his rope; and the reason is that the wisdom of the wisest dog is limited to business qualifications.  He is a hunter, and nature has endowed him with the requisite faculties, just as she has endowed the constructive spider and the bee.  Bees and dogs share the faculty of direction, enabling them to find their way home, a talent implying a very miracle of infallible and yet unconscious intuition, and in the strictest sense a one-sided business qualification.  The goose, the sturgeon, and the almost brainless tortoise possess the same gift in a transcendent degree; the oriole builds her first nest as skilfully as the last; the young bee constructs her hexagons with an ease and a uniform success that leave no possible doubt that the exercise of her talent is generically different from a function of reason.  Instincts may be far-reaching enough to defy the rivalry of human science, but they resemble loophole-guns, that can be fired only in a single direction.  The intuition that guides the turkey-hen to her nest does not enable her to find her way out of a half-open