Medical Herbs Catalogue



Botanical Name: Solanum tuberosum (LINN.)
Family: N.O. Solanaceae
Part Used: Edible tubers.

The Potato is nearly related to the Nightshades, belonging to the same genus, Solanum. Its flowers are very similar in form, but larger and paler in colour than those of Solanum Dulcamara.

The stalks, leaves and green berries possess the narcotic and poisonous properties of the Nightshades, but the tubers we eat (which are not the root, but mere enlargements of underground stems, shortened and thickened, in which starch is stored up for the future use of the plant), not being acted on by light, do not develop the poisonous properties contained by that part of the plant above ground. The influence of light on the tubers can be observed if in spring-time young green potatoes are exposed to daylight, when it will be found that they become poisonous and have a disagreeable taste.

The Potato was introduced into Europe early in the sixteenth century, being brought to Spain from Peru, and was first brought into England in 1586 from North America, the colonists sent out by Sir Walter Raleigh bringing it back with them from Virginia.

Gerard, in his Herbal published in 1597, gives a figure of the Potato, under the name of 'Potato of Virginia' - to distinguish it from the Sweet Potato. The Herbal contains a portrait of himself on the frontispiece holding in his hand a spray of the Potato plant with flowers and berries.

Though Sir Walter Raleigh was the first to plant the Potato, on his estate at Youghall, near Cork, it is said that he knew so little about it that he tried to eat the berries, and on discovering their noxious character, ordered the plants to be rooted out. It is said that the gardener in doing so, first learnt the value of their wholesome tubers.

From Ireland, the Potato was soon after carried into Lancashire, but for some time Potatoes were only grown as a delicacy for the epicure, not as food for the people. Both Gerard and Parkinson refer to them in this manner. The Puritans opposed their cultivation, because no mention of them could be found in the Bible, and it was not until the middle of the eighteenth century that potatoes became common in this country as a vegetable. As late as 1716, Bradley, in his Historia Plantarum Succulentarum, speaks of them as 'inferior to skirrets and radishes.'

The Potato is indigenous in various parts of South America, plants in a wild state having been found on the Peruvian coast, as well as on the sterile mountains of Central Chile and Buenos Aires. The Spaniards are believed to have first brought it to Europe, from Quito, in the early part of the sixteenth century. It afterwards found its way into Italy, and from thence it was carried to Mons, in Belgium, by one of the attendants of the Pope's legate. In 1598 it was sent from Mons to the celebrated botanist Clusius at Vienna, who states that in a short time it spread rapidly throughout Germany.

In the time of James I, potatoes cost 2s. a pound, and are mentioned in 1619 among the articles provided for the royal household. In 1633, when their valuable properties had become more generally known, they were noticed by the Royal Society, and measures were taken to encourage their cultivation in case of famine; but it was not till nearly a century after this that they were grown to any extent in England. In 1725 they were introduced into Scotland and cultivated with much success, first in gardens, and afterwards (about 1760), when they had become plentiful, in the open fields.

On the Continent, the adoption of the Potato as a vegetable met with considerable prejudice, and it did not become a general article of food for some time after it was in general use here. Gerard says: 'Bauhine saith that he heard that the use of these roots was forbidden in Burgundy for that they were persuaded the too frequent use of them caused the leprosie' - a belief without any foundation, for the disease is now confined to countries where the Potato is not grown, and its antiscorbutic properties have been proved.

Linnaeus for some time objected to the use of the Potato on account of its connexion with the Deadly Nightshade and Bittersweet. Solanine, the poisonous active principle contained in the stalks, leaves and unripe fruit, is very powerful, and has not yet been fully investigated. It is also present in the peel of the tuber, but is dissipated and rendered inert when the whole potato is boiled and steamed, and is decomposed by baking.

Constituents: The tuber is composed mainly of starch, which affords animal heat and promotes fatness, but the proportion of muscle-forming food is very small - it is said that 10 1/2 lb. of the tubers are only equal in value to 1 lb. of meat. The raw juice of the Potato contains no alkaloid, the chief ingredient being potash salts, which are present in large quantity. The tuber also contains a certain amount of citric acid - which, like Potash, is antiscorbutic - and phosphoric acid, yielding phosphorus in a quantity less only than that afforded by the apple and by wheat.

It is of paramount importance that the valuable potash salts should be retained by the Potato during cooking. If peeled and then boiled, the tubers lose as much as 33 per cent of potash and 23 per cent of phosphoric acid, and should, therefore, invariably be boiled or steamed with their coats on. Too much stress cannot be laid on this point. Peeled potatoes have lost half their food-value in the water in which they have been boiled.

The Potato is not only important as a valuable article of diet, but has many other uses, both medicinal and economic.

To carry a raw potato in the pocket was an old-fashioned remedy against rheumatism that modern research has proved to have a scientific basis. Ladies in former times had special bags or pockets made in their dresses in which to carry one or more small raw potatoes for the purpose of avoiding rheumatism if predisposed thereto. Successful experiments in the treatment of rheumatism and gout have in the last few years been made with preparations of raw potato juice. In cases of gout, rheumatism and lumbago the acute pain is much relieved by fomentations of the prepared juice followed by an application of liniment and ointment. Sprains and bruises have also been successfully treated by the Potato-juice preparations, and in cases of synovitis rapid absorption of the fluid has resulted. Although it is not claimed that the treatment in acute gout will cure the constitutional symptoms, local treatment by its means relieves the pain more quickly than other treatment.

Potato starch is much used for determining the diastatic value of malt extract.

Hot potato water has in years past been a popular remedy for some forms of rheumatism, fomentations to swollen and painful parts, as hot as can be borne, being applied from water in which 1 lb. of unpeeled potatoes, divided into quarters, has been boiled in 2 pints slowly boiled down to 1 pint Another potato remedy for rheumatism was made by cutting up the tubers, infusing them together with the fresh stalks and unripe berries for some hours in cold water, and applying in the form of a cold compress. The potatoes should not be peeled.

Uncooked potatoes, peeled and pounded in a mortar, and applied cold, have been found to make a very soothing plaster to parts that have been scalded or burnt.

The mealy flour of baked potato, mixed with sweet oil, is a very healing application for frost-bites. In Derbyshire, hot boiled potatoes are used for corns.

Boiled with weak sulphuric acid, potato starch is changed into glucose, or grape sugar, which by fermentation yields alcohol this spirit being often sold under the name of British Brandy.

A volatile oil - chemically termed Amylic alcohol, in Germany known as Fuselöl - is distilled by fermentation from potato spirit.

Although young potatoes contain no citric acid, the mature tubers yield enough even for commercial purposes, and ripe potato juice is an excellent cleaner of silks, cottons and woollens.

A fine flour is prepared from the Potato, and more used on the Continent than in this country for cake-making.