The general plan of the old house is the same as the new, though differing in some minor details. The most interesting thing in connection with this at present is the electric light experiment. The house is divided near the middle by a tight • board partition, and in one room is a Brush arc-lamp. The complete plant is owned by the horticultural department. A six-horse power engine and Westinghouse dynamo is in the cellar of the potting-house to supply the current. This is kept running all night by a night engineer, with a view to determining whether the light has any influence upon the growth of plants. The lower table is devoted to lettuce, the lower center one to peas . of. different varieties, the next to salad plants, and the upper one to radishes and carrots in alternating blocks. Care has been taken to have all the conditions as nearly identical as possible in each division, in order to make the list reliable. The tables all run through both rooms. Some machines have been devised for measuring the growth of plants by the hour by means of clockwork.

This is a very important experiment, and entirely new in a practical way. It is of special moment to persons in cities or wherever electric lights are used, and especially to those who have much surface under glass. It is by far the largest experiment of the kind which has ever been carried on, and in fact the only one destined to be of much practical value. Plants usually grow ordinarily at night, and it will be of great interest to note what their behavior is when subjected to light continuously; whether they will grow under the electric light the same as in darkness or change their habit of growth entirely.

If they change, during what portion of the day will it be most rapid ? Are the properties of electric light and sunlight so similar that the operations of the plant must be uniform throughout the whole twenty-four hours, and if so will the effect be to make growth continuous and accelerated or to retard it ? It is to assist in determining these and other points that the contrivances for measuring the growth each hour were gotten up. It is probable that later on trials will be made in the matter of substituting the electric light for sunlight altogether. Is it simply light and heat which plants need, or are there properties essential to growth in the sun's rays which artiflcial light does not possess ?

A considerable portion of the work of growing and caring for the plants in these houses is done by students taking practical work in horticulture. One student is making some extended trials with herbaceous grafting, using many of the different methods of inarching and grafting on such plants as coleus, tomato and potato. Part of his trials are made with grafting wax and part with sphagnum moss as a protecting material. Another is doing some original work in the study of the striking of cuttings by experimenting with many plants, taking off the callus when formed and starting the cutting again, preserving the callus in alcohol.

It is designed to add another house the coming season, as indicated by the cut, N, in order to give better opportunity for the work of students without encroaching upon the room of experimentation.

Fred. W. Card.

Pennsylvania.