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See also:POTASSIUM [See also:symbol K (from kalium), atomic See also:weight 39.114 0=16)] , a metallic chemical See also:element, belonging to the See also:group termed the metals of the alkalis . Although never found See also:free in nature, in See also:combination the See also:metal is abundantly and widely distributed . In the oceans alone there are estimated to be 1141,X 1012 tons of sulphate, K2SO4, but this inexhaustible See also:store is not much See also:drawn upon; and the " See also:salt gardens " on the See also:coast of See also:France lost their See also:industrial importance as potash-producers since the deposits at See also:Stassfurt in See also:Germany have come to be worked . These deposits, in addition to See also:common salt, include the following minerals: sylvine, KCI; carnallite, KCl•MgC12.6H2O (transparent, deliquescent crystals, often red with diffused See also:oxide of See also:iron); kainite, K2SO4•MgSO4•MgC126H2O (hard crystalline masses, permanent in the See also:air); kieserite MgSO4•H20 (only very slowly dissolved by See also:water); besides polyhalite, MgSO4•K2SO4.2CaSO4.2H2O- See also:anhydrite, CaSO4; salt, NaCl, and some See also:minor components . These See also:potassium minerals are not See also:con-fined to Stassfurt; larger quantities of sylvine and kainite are met with in the salt mines of Kalusz in the eastern Carpathian Mountains . The Stassfurt minerals owe their industrial importance to their solubility in water and consequent ready amenability to chemical operations . In point of See also:absolute See also:mass they are insignificant compared with the abundance and variety of potassiferous silicates, which occur everywhere in the See also:earth's crust; See also:orthoclase (potash See also:felspar) and potash See also:mica may be quoted as prominent examples . Such potassiferous silicates are found in almost all rocks, both as normal and as See also:accessory components; and their disintegration furnishes the soluble potassium salts which are found in all fertile soils . These salts are sucked up by the roots of See also:plants, and by taking See also:part in the See also:process of See also:nutrition are partly converted into oxalate, tartrate, and other organic salts, which, when the plants are burned, are converted into the carbonate, K2CO3 . It is a remarkable fact that, although in a given See also:soil the soda-content may predominate largely over the potash salts, the plants growing in the soil take up the latter: in the ashes of most See also:land plants the potash (calculated as See also:K20) forms upwards of 90% of the See also:total See also:alkali . The proposition holds, in its See also:general sense, for See also:sea plants likewise . In ocean water the ratio of soda (Na2O) to potash (K20) is See also:loo : 3.23 (Dittmar); in See also:kelp it is, on the See also:average, too : 5.26 (See also:Richardson) .
Ashes particularly See also:rich in potash are those of burning nettles, See also:wormwood (See also:Artemisia absinthium), tansy (Tanacetum vulgare), See also:fumitory (Fumaria officinalis), and See also:tobacco
.
In fact, the ashes of herbs generally are richer in potash than those of the trunks and branches of trees; yet, for obvious reasons, the latter are of greater industrial importance as See also:sources of potassium carbonate
.
According to See also:Liebig, potassium is the essential alkali of the See also:animal See also:body; and it may be noted that See also:sheep excrete most of the potassium which they take from the land as sweat, one-third of the See also:weight of raw See also:merino consisting of potassium compounds
.
To See also:Sir See also:Humphry See also:Davy belongs the merit of isolating this element from potash, which itself had previously been considered an element
.
On placing a piece of potash on a See also:platinum See also:plate, connected to the negative of a powerful electric See also:battery, and
See also:ordinary merit
.
Curious if not very See also:artistic bills have been produced in See also:Russia; and in See also:Austria See also:good See also:work has been done by Orlik, Schliessmann, See also:Oliva and Hynais
.
In the See also:United States of See also:America, however, with the exception of some designs by Matt See also:Morgan, few posters of artistic See also:interest were produced before 1.889, in which See also:year See also:
Others who have achieved success in it include Maxfield Parrish, Ethel See also:Reed, Will Carqueville, J
.
J
.
See also:Gould, J
.
C
.
Leyendecker, See also:Frank Hazenplug, See also: C . See also:Bunner and A . Jaccacci, The See also:Modern Poster (New See also:York . 1895) . ' (C . |
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