IN Prof. Parker's very valuable and interesting paper (vol. xxiv. p. 54) 3 he says: “The consequences of setting large classes of young boys to make oxygen, or to take a specific gravity … each for himself, might prove rather subversive of order than conducive to improvement.” It may be interesting to some of your readers to know that at Clifton College we have lately tried the experiment of turning some of our ordinary physics classes, numbering from twenty-four to thirty boys, bodily into the physical laboratory, where they work at weighing, measuring, finding specific gravities and such matters, under the control of a single master. The boys work in pairs, each with a little manual of instruction, and each pair with a separate cupboard of cheap apparatus. Two such classes are taken by Mr. Worthington and myself, and we are both agreed that whatever difficulties we may feel, we have none in the matter of discipline. On the contrary, the boys are with scarcely an exception most keen and eager at this work. I understand that similar classes in practical chemistry will shortly be set on foot by Mr. Shenstone in our chemical laboratory.