482 MEDICAL BOTANY. 



wineglassful, three or four times a day, until the appearance of slight nar- 

 cotic symptoms indicate that the remedy is acting on the system. 



Many other species of Solanum have been employed medicinally, espe- 

 cially the S. nigrum or common Nightshade, a variety of which, the virgi- 

 nianum, is so abundant in this country. It appears to possess the same 

 properties as the Bitter-sweet, but in a greater degree; this may be accounted 

 for by the fact that Solanina exists in it in a greater proportion. Gataker, 

 who tried it extensively, states that he found it a powerful narcotic, sudorific, 

 cathartic, and diuretic (Obs. on Solanum), and Orfila ( Toxicol. Gen. ii. 190), 

 says he found an extract of it equal in power and energy to lactucarium. 

 It has been employed in the same description of cases as the Bitter-sweet. 

 The leaves are used in Brazil in poultices or decoction to painful wounds. 



The S. tuberosum or Potato is of more interest as an article of diet than 

 as a medicinal agent, though the stalks possess the narcotic qualities of the 

 other species, and even the tubers contain a certain portion of the alkaloid; 

 this appears to be confined to their epidermis, and is greatly increased in 

 quantity where the Potato is exposed for any time to the action of the light, 

 in which case the epidermis assumes a greenish colour, and the poisonous 

 principle is so much developed as to render the root unfit for food. The 

 water in which potatoes are boiled contains solanina. The Potato contains 

 much starch, which is contained in a cellular tissue; this starch, which is the 

 principal nutritious ingredient of the tuber, is used as a substitute for arrow- 

 root, and is also so manufactured as to resemble and to be sold for sago. 

 The Potato in a raw state eaten as a salad with vinegar has proved of much 

 benefit on shipboard as a preventive of scurvy ; it sometimes acts on the 

 bowels, and even induces slight narcotic symptoms. An extract of the leaves 

 is highly spoken of by Mr. Dyer in chronic rheumatism and painful affections 

 of the stomach and bowels; he is of opinion that it ranks between Conium and 

 Belladonna (Pharm. Jour. i. 590). Much difference of opinion has existed 

 among naturalists as to the native country of the Potato, and from what 

 place and by whom it was first carried to Europe. Some confusion has 

 arisen from confounding it with the Batatas or sweet potato. The first defi- 

 nite record of it is by P. Cieca {Chronica di Peru) in 1553; he says the na- 

 tives of Peru have, besides maize, a tubercular root, they call Papas. After this 

 it is noticed by Gomara in 1554, and Cardan (De Rerum, var. 16) in 1557. 

 It is usually stated that it was carried to England from Virginia or Carolina 

 by Sir Walter Raleigh in 1586, but this is not satisfactorily ascertained. Two 

 years afterwards, P. de Sivry sent Clusius two tubers, which were planted, 

 and from the plants, Clusius described and gave the first representation of it 

 in 1599. (Plant. Par. 1. iv. 79.) It has been found wild in Peru by Dr. 

 Baldwin (Reliquice Baldwin), and by Pavon (Jour. Sci. and Arts, No. 9, 138). 



For further information on the subject, the following papers may be con- 

 sulted with advantage: Dunal, Histoire Naturelle et Medicale des Solanum, 

 1813, most of the historical portions of which are taken from Bauhin (Hist. 

 Plant, iii. 621); and an excellent synopsis by G. Ord, in the A?mals of 

 Nat. Hist. xvii. 1846. Besides the uses of the Potato as an article of diet, 

 the stalks furnish a large quantity of potash, and it is said that if the stalks 

 were appropriated to this manufacture, that they would supply most that is 

 required in commerce. They also afford a bright yellow dye, which is 

 obtained by cutting them when in flower, and bruising and pressing them to 

 extract the juice. (Jour. Sci. and Arts, v.) 



The S. lycopersicon (Lycopersicum esculcntum) or Tomato, whose esculent 

 fruit is in such general use in this country, is also a native of South America. 

 The leaves, which have a nauseous and narcotic odour, contain an alkaloid 



