It is not possible to convey to the reader, by means of mere description, anything approaching an adequate notion of the surpassing gracefulness of the entire work of this epoch. The eye must be made the channel to the mind. If the work is present, then, with the aid which these remarks will afford, the reader may gain, by careful study, much valuable insight into the beauties and genius of this famous artist, together with much useful information. But during this period of his maturity, even, we find that Stradivari did not absolutely confine himself to making instruments as near as possible alike; on the contrary, it is easy to point out certain variations, the meaning of which he doubtless well understood. We find him guided throughout this period by his usual ideas as regards grandeur of outline and degrees of thickness; but the rotundity of the model, the shape that he gave to the sound-hole, the method of setting the sound-hole in the instrument, although, as before remarked, all executed with a breadth of purpose which his earlier efforts fail to show, may be cited as points in which he varied. I have no hesitation in hazarding an explanation of the reasons that prompted him to these differences of construction. It is my firm conviction that these great makers had certain guiding principles as regards the nature and qualities of the wood they used, and that Stradivari, in particular, made the subject a special study. If this be granted, I do not think there is any great difficulty in understanding the meaning of the differences pointed out. If Stradivari constructed his instruments upon philosophical principles, the chief element of variation in the treatment of any particular instrument must have been the difference of _quality_ in the material; it is evident that a method eminently successful when applied to wood of a certain texture and character, would ensure as eminent a failure if applied indiscriminately in all cases. To obtain wood sufficient for two bellies that should be alike in every particular is impossible, though cuttings should be made from the same piece; and we find that the more the material varies in its nature, so much the greater the variations--a fact which helps the view advanced considerably. In another place I have stated that scarcity of sycamore in the days of these old makers is impossible to understand, but scarcity of a particular _kind_ of sycamore is easy to comprehend. He might have had a cartload of wood handsome in appearance; but handsome wood combined with acoustical properties he deemed needful, was another matter. With what extraordinary care he permitted himself to use the lovely wood he did possess! There are several instances where he has used, during one year, four or five distinct cuttings of wood, more particularly as regards the sycamore. These several cuttings include often the handsomest and the plainest. A year or so later we find him again making use of wood from the same