The drying of plants may be much quickened by dividing them into packets of 8 or 10 packets only, with very little paper between, and pressing them between two frames furnished with a wire grate tied up by strings; a layer of four or five leaves of paper should be placed on each side, immediately under the grate, to render the pressure more uniform and keep the plants from crisping; if these small packets are exposed to the sun or a current of air, the plants dry rapidly, often before the paper is changed that contains them; but unless there is a great number of these frames, it is impossible to dry but a small number of plants, and this process would be especially useful for those persons to whom the formation of an herbal is but an accessory occupation. Botanists who wish to dry many plants without using much paper should place packets of 15 or 20 plants, arranged as we have just pointed out, in a stove with a current of air, heated up to 50 centigrades by a lamp placed below, and separated from the plants by a cross partition of punctured plate. In twelve or twenty four hours the specimens are perfectly dry. This process, first successfully employed in Paris by M. Doyere, is most useful in warm and damp climates, and for plants difficult to dry; it is easily employed in scientific voyages. Bamboo frames, found everywhere in tropical climates, replace excellently frames and bars of iron. There is another more speedy process which requires much less paper, but preserves less perfectly the dried specimens. It only needs a dry and spacious room. The flowers are placed in a simple sheet of paper and pressed; then the sheets are spread out, for the night, on the floor, and, when dry, pressed again. This process it not so good as the former, and should be made use of only when there is a lack of paper. This is all the art of making herbals; and every intelligent traveller knows how to suit his process to circumstances. In damp times and regions, it is well to quicken the process of drying. Paper perfectly dry should only be used, and changed often. The paper should be dried in a warm oven, where bread has just been baked. Watery plants, such as bulbs, orchides, etc., continue green in herbals several months after they are placed in them. It is well to plunge them in boiling water for one minute, or, still better, to put them in alcohol for a couple of hours; then they should be taken out and placed between two leaves of brown paper, where it dries easily, as the action of boiling water or alcohol has destroyed the life of the plant. There are plants whose leaves or flowers easily break after drying; in such cases, all the parts should be sent separately.