There is a group of succulent roots which contain considerable watery juice, and on this account are usually eaten fresh, for if kept long they become dry and less palatable, or are apt to decay; with care, however, they may be preserved in their natural state for a considerable period. They are very digestible, and when thoroughly boiled are nutritious. They are carrots, parsnips, turnips, salsify, and radishes.

Carrots.consist of upward of 85 per cent of water, with a small proportion of salts, 8 per cent of carbohydrates with some sugar, and about 1 per cent of protein. The outer layers of the carrot contain a material called pectin that can be obtained as a jelly and mixed with fruit or meat jelly for flavouring invalid diet.

Young carrots, when soft and friable, if boiled are very tender and highly flavoured, and constitute a nutritious food.. In France and Germany they are more popular than in this country and are cooked with other vegetables, although somewhat at the expense of the flavour of the latter. At the baths of Vichy they form a part of the daily breakfast.

Parsnips contain the sugar of starch with a large percentage of water, and they are sometimes fermented into an alcoholic beverage. They are a wholesome although less used food than carrots. The parsnip contains over 90 per cent of water and only 6 per cent of starch and sugar, with 1 per cent of protein, besides other materials. It is a rather strongly flavoured vegetable, and bulky in proportion to its nutritive value. It is extensively used for feeding cattle, and when young and properly cooked by prolonged boiling and seasoning it is a good food. It should be particularly avoided by those persons in whom there is any tendency to flatulency, which, like the legumes, it is apt to produce.

Turnips are less nutritive than either carrots or parsnips. They should never be eaten by the sick.

Kohl rabi, or turnip-root cabbage, yields an overground turnip, which is somewhat astringent.

Salsify, or oyster plant, is a root which has a mild sweet flavour somewhat similar to the parsnip, and is an excellent food of easy digestibility.

Radishes, which are not unlike turnips in composition, contain a large percentage of water and a comparatively small amount of starch. This vegetable is of no special value for nutrition, and serves chiefly as a relish. Being usually eaten raw, it is difficult of digestion, and is apt to produce eructations. It is rendered more digestible by cooking. It has some reputation as an antiscorbutic.