his life he gradually increased his breadth of manner. He was still magnificent in general expression, but the intimate details which produced such glorious effects in the great Amsterdam picture, and fifty or more of his single portraits, could not be obtained with hog's hair.[8] Disconnecting then the work of the artist with inspiration or other psychological force, we may now enquire what is mean by "Genius," "Natural gift," or other term used to explain the power of an artist to produce a great work? It would appear that the answer is closely concerned with the condition of the sensorial nerves at birth, and the precocity or otherwise of the infantile imagination. From the fact that we can cultivate the eye and ear so as to recognize forms of harmony which we could not before perceive, and seeing that the effect of this cultivation is permanent, it follows that exercise must bring about direct changes in the nerves associated with these organs, attuning them so to speak, and enabling them to respond to newer harmonies arising from increased complexity of the signs used.[9] It is matter of common knowledge that the structure of the sensorial nerves varies largely in different persons at birth, and when a boy at a very early age shows precocious ability in music or drawing, we may properly infer that the condition of his optic or aural nerves is comparatively advanced, that is to say, it is much less rudimentary than that of the average person at the same age; in other words accident has given him a nerve regularity which can only be gained by the average boy after long exercise. The precocious youth has not a nerve structure superior in kind, but it is abnormally developed, and so he is ahead of his confreres in the matter of time, for under equal conditions of study he is sooner able to arrive at a given degree of skill. But early appreciation of complex harmony, and skill in execution, are not enough to produce a great artist, for there must be associated with these things a powerful imagination. While the particular nerves or vessels of the brain with which the imagination is concerned have not been identified, we know by analogy and experience that the exercise of the imagination like that of any other function, is necessary for its development, and according as we allow it to remain in abeyance so we reduce its active value. Clearly also, the seat of the imagination at birth is less rudimentary in some persons than in others. From these facts it would appear that when both the sensory nerve structure and the seat of the imagination are advanced at birth, then we have the basis upon which the precocious genius is built up. With such conditions, patient toil and deep study are alone necessary to produce a sublime artist. Evidently it is extremely rare for the imagination and nerve structure to be together so advanced naturally, but commonly one is more than rudimentary, and the deficiency in the other is compensated for by study.[10]