354 



POTASSH M 



POTATO 



or in the flame of siiirit, luu been already noticed. 

 (4) The spectrum of a flame containing potassium 

 exhibits a characteristic bright line at the c\n. m. 

 limit of the red, ami nnoilirr one at the opposite 

 >i.det limit nf the Spectrum (ij.v.). 



ID medicine the IbBewiag compounds are used : 

 Cauttic Pota*)i, or Itutlmte of I'utiufi, KOH, which 

 occurs in hard white pencils. From ita power of 

 dissolving the animal tissues, it is sometimes used 

 as a caustic, although ila great deliquescence rendeni 

 it somewhat difficult to localise lUi action to the 

 desired spot. In bites of venomous serpents, mad 

 dogs, &c. it may be applied with advantage, and 

 11 i- useful in destroying warteand fungoii' growths 

 of various kinds. Solution of Potash, commonly 

 known as Liquor potautr, is obtained by the pro- 

 cc :ilrcjul\ -i\.-ni..i [in- |.i. -|. .1 .iti.iji ..i hv.ii.il.- ot 

 potash. Liquor potassif, in combination with a 

 tonic infusion, U of service in canes of dyspepsia 

 which are accompanied with excessive acidity of 

 tin- stomach, such, for example, as often occur in 

 habitual spirit-drinkers. It is also frequently given 

 with the \ lew of icndei in;: the urine alkaline, or of 

 diminishing its acidity in cases in which that 

 secretion is too acid. The usual dose is ten drops, 

 gradually increased to as much as a fluid drachm. 

 Acetate of Potash, KC,H,OL, U obtained by the 

 action of acetic acid on carbonate of potash, and 

 occurs in white foliaceous satiny masses. - In its 

 passage through the system it is converted into 

 carbonate, and thus renders the urine alkaline. 

 In small doses, as from a scruple to a drachm, it 

 acts as a diuretic, and is of service in some forms 

 of dropsy. Combined with other potass-salts, it is 

 much given in acute rheumatism. The two car- 

 bonates and the sulphurated potash have been 

 already referred to. 



The Chlorate of Potash has come much into use 

 as a popular remedy for sore throats. For this 

 purpose it is usually employed in the form of com- 

 pressed pellets, which are allowed to dissolve 

 slowly in the mouth. 



Potato (Solatium tuberofum ; see SOLANUH), 

 one of the most important of cultivated plants, and 

 in universal cultivation in the temperate parts of 

 the globe. It is a perennial, having herbaceous 

 stems, 1 to 3 feet high, without thorns or prickles ; 

 pinnate leaves with two or more pair of leaflets 

 and an odd one, the leaflets entire at the margin ; 

 flowers about an inch or an inch and a half in 

 breadth, the wheel-shii]ied corolla being white or 

 purple, and more or less veined, followed by globu- 

 lar, purplish fruit, of the size of large goose- 

 berries ; the roots producing tubers. The herbage 

 lias a slightly narcotic smell, although cattle do not 

 refuse to eat a little of it, and the tender tops are 

 used in some countries like spinach. The tubers 

 are, however, the only valuable part of the plant. 



It was long customary to speak of the potato as 

 a native of mountainous district- of tropical and 

 subtropical America; but it has never been clearly 

 determined where it is really indigenous, and where 

 it has spread aftr being introduced by man. 

 Hunibnldt doubted if it had ever been found truly 

 wild ; but subsequent travellers, of high scientific 

 reputation, express themselves thoroughly satisfied 

 on this point. It has been rendered certain that 

 long before the Spaniards reached the New World 

 the potato was cultivated by the Incas and otln-r 

 Anifean nut ions. It seems to have been first 

 brought t<> Kiiro|M. by the Spaniards, from the niMgh- 

 iMHirliood of l^uito, in the lieginning of the n;ih 

 century, and to have spread from Spain into the 

 Netherlands, Borgundy, mid Italy, but only to be 

 cultivated in a few gardens as a curiosity, and not 

 for general UM as an article of food. It U sai.l to 

 ln.e been brought to Kngland from Virginia by 

 Kir John Hawkins in 1563; and, again, in 1586 by 



Sir Francis Drake, to whom indeed a statue, as 

 the introducer of the potato, was erected at Oflen- 

 burg, in liaden, in 1853. Anyhow, it cannot have 

 attracted much notice; aim though lialeigh is 

 believed to have planted potatoes both at his 

 Devonshire birthplace Hayes, and on his Munster 

 estates, it was a long time before they began to be 

 extensively cultivate!. It long received throughout 

 almost all European count ties the same name 

 with the Batatas or Sweet Potato (q.v. ), which 

 is the plant or tuber meant by Engli-h writers 

 down t the middle of the 17th century in their 

 use of the name potato. Gerard, in his fferball, 

 published in I.V.C. jjive- a figure of our potato 

 under the name of Batata I try in tana ; but so 

 little were its merit* appreciated that it is not 

 even mentioned in the Complete Gardener of 

 London and Wise, published more than a cen- 

 tury later, in 1719; whilst another writer of the 

 same time says it is inferior to skirret and 

 radish 1 It began, however, to l>e imagined that it 

 might be used with advantage for feeding 'swine 

 or other cattle,' and by-and-by that it might be 

 useful for poor people, and for the prevention of 

 famine on failures of the grain-crops. The Koyal 

 Society took up this idea, and in 1663 adopted 

 measures for extending the cultivation of the 

 potato, in order to the prevention of famines. To 

 this the example of Ireland in some measure led, 

 the potato having already come into cultivation 

 there to an extent far greater than in any other 

 European country, and with evident advantage to 

 the people. From Ireland the cultivation of the 

 potato was introduced into Lancashire about the 

 end of the 17th century, soon became general there, 

 and thence spread over England ; so that before 

 the middle of the 18th century it had become im- 

 portant as a field-crop, which it became in the 

 south of Scotland some twenty or thirty years 

 later, about the same time in Saxony and some 

 other parts of Germany, but not until the later 

 part of the century in some other parts of Germany 

 and in France. In France the potato was long 

 supposed to cause leprosy and fevers, and the 

 extension of its culture was mainlv due to the exer- 

 tions of Parmentier (1778). In Prussia Frederick 

 the Great took an interest in it, and promoted it 

 by compulsory regulations. 



The potato U of great importance as affording 

 food both for human l>eings and for cattle ; and 

 next to the principal cereals is the most valuable 

 of all plants for human food. It is also used for 

 various purposes in the arts. No food-plant is 

 more widely diffused ; it is cultivated in subtropical 

 countries, and struggles for existence in gardens 

 even within the Arctic Circle, yielding small and 

 watery tubers, although the effects of late spring 



froste, or early autumnal frosts, upon it.- foliage 

 often prove that it is a plant properly belonging to 

 a climate milder than that of most part - of Britain. 



No more imiiortant event of its kind has ever taken 

 place than the general introduction of potato cul- 

 ture into the husbandry of Britain and oilier Euro- 

 pean countries. It lias exercised a beneficial 

 influence on the general welfare of the people, and 

 has increased the national wealth, notwithstand- 

 ing the occasional occurrence of famine and distress 

 ( notably in the years I sill and 1847 ) in Ireland and 

 elsewhere from the failure of the crop. The results 

 due mainly to excessive and imprudent cultiva- 

 tion of the potato confirmed two great laws, that 

 plants long very extensively or almost exclusively 

 cultivated in any district, however successfully 

 they may lie cultivated fora time, are sure to fail 

 at last; and that the exclusive, or almost exclusive, 

 dependence of a people on one source or means of 

 Mip|Mirt is unfavourable to their welfare in respect 

 to all their interests. 



