The work embodied in this series of models is the most important of all to the pupil. Eleven years is about the average age of pupils who are able to begin it, but it would not be right to say that all of that age would be able to do the work, nor would it be proper to exclude all pupils who are under that age, for many are more apt at the age of nine than others at the age of fourteen. This depends greatly upon inheritance, natural brightness and environment. At this particular age character is easily moulded; the hand and eye easily trained, and thoughts easily directed. Every pupil should be allowed to proceed with the work as fast as he can, and do excellent work, for every one should be kept at his best all the time.