Here is an account of his method of teaching Arithmetic, taken from the introduction to a little work on the subject, published by himself in 1809: "I divide my pupils," he says, "into separate classes, according to their progress. Each class has one or more sums to produce every day, neatly wrought upon their slates: the work is carefully examined; after which I command every figure to be blotted out, and the sums to be wrought under my eye. The one whom I happen to pitch upon first, gives, with an audible voice, the rules and reasons for every step; and as he proceeds the rest silently work along with him, figure for figure, but ready to correct him if he blunder, that they may get his place. As soon as this one is finished, the work is again blotted out, and another called upon to work the question aloud as before, while the rest again proceed along with him in silence, and so on round the whole class. By this method the principles are fixed in the mind; and he must be a very dull boy indeed who does not understand every question thoroughly before he leaves it. This method of teaching Arithmetic possesses this important advantage, that it may be pursued without interrupting the pupil's progress in any other useful study. The same method of teaching Algebra has been used with equal success. Such a plan is certainly very laborious, but it will be found successful; and he that is anxious to spare labour ought not to be a public Teacher. When boys remain long enough, it has been my custom to teach them the theory, and give them a number of curious questions in Geography, Natural Philosophy and Astronomy, a specimen of which may be seen in the questions placed before the Appendix."