2. _On Cutting unprepared Vegetable Tissues._—There are some few substances, however, which may with more or less success be cut into sections whilst in their natural condition. Such objects are to be found in the vegetable world in certain kinds of leaves and allied structures, whilst in the animal kingdom they are principally represented by the various internal organs of man and the lower animals. Special directions are given in text-books for the preparation of sections of leaves and similar substances. For instance, it is recommended to lay the leaf, etc., on a piece of fine cork, and with a sharp knife to shave off thin slices, cutting down upon the cork. Another plan is to place the leaf, etc., between two thin layers of cork, and cut through the mass. No method, however, is at once so simple and successful as the process of imbedding in paraffine. To do this, it is necessary to make a paper mould by twisting a strip of stout writing paper round a ruler, and turning-in the paper over the end of the ruler. This mould, the height of which may vary from an inch to an inch and a half, should now be about half filled with melted paraffine mixture (§ 11), the leaf or other object plunged into it, and held in position by small forceps till the paraffine has become sufficiently solidified to yield it a support. More of the paraffine mixture is now poured in until the specimen is thoroughly imbedded; the whole is to be put away in a cold place for an hour or so, when the mass will be found sufficiently firm to be cut with ease. Sections may be made with a razor kept constantly wetted with water, or, if the preservation of colour be no object, methylated spirit may be employed for the purpose. As the subsequent treatment of such sections in no wise differs from that required by those cut in the microtome, we shall defer its consideration until that method of section has been described (§ 12).