Part 56. Essences are flavoring substances extracted from plants in various ways, often dissolved in water or alcohol, and always in liquid form. Peppermint obtained from the whole plant (Fig. 146), wintergreen from the leaves and fruit (Fig. 147), vanilla from the pods (Fig. 148 I), lemon from the rind of the fruit (Fig. 106), and rose from the petals (Fig. 148 II, 148 III) are familiar examples.

In peppermint, wintergreen, lemon, and rose the flavoring substance is a volatile oil. In vanilla it is a peculiar crystalline substance called vanillin, which curiously enough occurs also in the sugar-beet root, and is manufactured artificially from oil of cloves and from pine wood. But these artificial products are inferior in flavor to the natural product extracted from the vanilla "bean."

The oil of wintergreen is likewise manufactured artificially, but in this case the artificial product is indistinguishable from the natural one. Unlike most oils this sinks in water, being indeed the heaviest known of volatile oils. It is a powerfully acting substance possessing poisonous properties when used in more than very small amount.

Fig. 146, I. Peppermint (Mentha piperita, Mint Family, Labiatoe). Flowering top. (Baillon.) A perennial herb, growing 1 m. tall, aromatic; leaves bearing numerous minute volatile oil glands; flowers pale purplish; nutlets seldom formed.

Fig. 146, I.-Peppermint (Mentha piperita, Mint Family, Labiatoe). Flowering top. (Baillon.)-A perennial herb, growing 1 m. tall, aromatic; leaves bearing numerous minute volatile oil glands; flowers pale purplish; nutlets seldom formed.

Fig. 146, II. Peppermint. Flowers, enlarged about five times, showing the two sizes often present.

Fig. 146, II.-Peppermint. Flowers, enlarged about five times, showing the two sizes often present. (Baillon.)

Fig. 147. Wintergreen (Gaultheria procumbens, Heath Family, Ericaceae). Plant in flower and fruit, reduced. Corolla with attached stamens spread out. Pod, cut across. (Britton and Brown.) An undershrub growing about 5 15 cm. tall; leaves evergreen; flowers white; fruit bright red, consisting of the fleshy aromatic calyx enclosing a dry pod. Native home, North America.

Fig. 147.-Wintergreen (Gaultheria procumbens, Heath Family, Ericaceae). Plant in flower and fruit, reduced. Corolla with attached stamens spread out. Pod, cut across. (Britton and Brown.)-An undershrub growing about 5-15 cm. tall; leaves evergreen; flowers white; fruit bright red, consisting of the fleshy aromatic calyx enclosing a dry pod. Native home, North America.

Fig. 148, I. Vanilla (Vanilla planifolia, Orchid Family, Orchidaceoe.) Flowering branch, reduced in size, showing leaves and air roots. A, lip of the flower, and along its back the column formed of style and stamens grown together. B, C, column, side view and front view, showing anthers (a) and rudimentary stamen (s). D, top of column, cut lengthwise through anthers. E, seed, much enlarged. (Berg and Schmidt.) A tall, climbing herb attaching itself to trees by means of air roots; leaves thick; flowers yellow; fruit a pod ripening in two years, 16 30 cm. long, 7 10 mm. thick. Native home, Mexico.

Fig. 148, I.-Vanilla (Vanilla planifolia, Orchid Family, Orchidaceoe.) Flowering branch, reduced in size, showing leaves and air-roots. A, lip of the flower, and along its back the "column" formed of style and stamens grown together. B, C, column, side view and front view, showing anthers (a) and rudimentary stamen (s). D, top of column, cut lengthwise through anthers. E, seed, much enlarged. (Berg and Schmidt.) A tall, climbing herb attaching itself to trees by means of air-roots; leaves thick; flowers yellow; fruit a pod ripening in two years, 16-30 cm. long, 7-10 mm. thick. Native home, Mexico.