POT 



POT 



pots set in a furnace : these are kept 

 full several days. When the lluid 

 bei'omes black and of the consistence 

 of thick molasses, it is subjected to 

 the highest heat of a wood tire for 

 some hours ; by this means much of 

 the combustible matter is burned. 

 As soon as the fused matter becomes 

 quiet it is dipped out by iron ladles 

 into iron pots, where it congeals ; 

 this, broken into pieces and barrelled, 

 forms commercial potash. The lye 

 should be sufficiently strong to bear 

 an egg before being evaporated. 

 Pearlash is made by transferring the 

 black potash into a reverberatory fur- 

 nace, and stirring it while hot : this 

 is continued until it acquires a whi- 

 tish colour. 



Composition. — American potash 

 consists of 85-7 parts caustic potas- 

 sa, 15 4 sulphate of potassa, 20 com- 

 mon salt, 11-9 carbonic acid and wa- 

 ter, and 2 insoluble matter in 115 

 parts. Pearlash contains 75-4 caus- 

 tic potash, 80 sulphate, 0-4 common 

 salt. 30 8 carbonic acid and water, 

 6 insoluble matter in 115 parts. 



Amount of pure potash in 1000 lbs. 

 of wood : in elm and maple, 39 lbs. ; 

 willow, 28 lbs. ; oak and beech, H 

 lbs. ; poplar, | lb. : the spray and 

 young branches are richest in ashes. 

 The varieties of pine seldom furnish 

 half a pound to the 1000 of timber. 



POTASSIUM. The metallic basis 

 of potash ; it is white and brilliant, 

 but soft as wax, lighter than water, 

 sp. gr. "86, and spontaneously inflam- 

 mable on water ; symbol, K. ; propor- 

 tional, 393. Its compound with 1 

 equivalent o.xygen, potash, is one of 

 the most important chemical agents : 

 a powerful base and an alkali. 



Potash is very soluble in water, 

 neutralizes acids, discharges the col- 

 our of red litmus, converting it into 

 blue ; it is also soluble in alcohol. 

 It unites detinilely with water, form- 

 ing the hydrate, or fused potash, con- 

 taining 47-3 potash, and 9 parts wa- 

 ter. Potash combines with nearly all 

 acids ; by the agency of heat it also 

 dissolves silica, being converted into J 

 silicate of potash. Its prominent 

 salts are the nitrate, carbonate, sul- 



phate, and muriate (chloride of po- 

 tassium). 



In the mineral kingdom it exists 

 abundantly, forming 10 to 20 per cent, 

 of many minerals, as mica, feldspar, 

 lava, and green sand. In these it is 

 insoluble, and in tlie form of silicate; 

 but it becomes slowly dissolved by 

 water containing carbonic acid. In 

 plants it is also abundant, especially 

 in the grasses and cerealia ; the vine, 

 oak, willows, maples, cruciferous and 

 chenopodiaceous plants contain a con- 

 siderable proportion. It is found in 

 urine, and in other animal excretions. 



POTATO {Solanum tuberosum, 

 Linnaeus). Varieties: "Of the better 

 kinds, we may enumerate the follow- 

 ing ; 



" 1. Kidneys, or Foxites, white 

 flesh, rather small, and seemingly de- 

 teriorating, as an old variety. 



"2. Pink Eyes, white flesh, rather 

 kidney- shaped, yield well, and are yet 

 in their prime. 



" 3. St. Helen.\, very similar in 

 flesh, shape, colour, and quality to 

 the foregoing, without the pink eyes 

 or blotches : to us a new variety. 



" 4. Early Kidneys, real kidney- 

 shaped, smooth, white, and of fair 

 size : the best early variety. 



" 5. Mercer, well-known and de- 

 servedly liked. 



" 6. Sadlt St. Marie : the true 

 kind large, long, dark-coloured, and 

 good. 



" 7. Liverpool Blues : coloured, 

 good size, and productive. Boil white, 

 and may be placed in the first class 

 for the table. 



" The foregoing we esteem the best 

 kinds. There may be other kinds 

 equally good, and some that we have 

 enumerated may be known by other 

 names. The Forty-fold has been 

 highly commended for its productive- 

 ness and good qualities, with what 

 truth we will not venture to say. 



"In this latitude the potato is bet- 

 ter, both as to product and flavour, 

 when grown on a moist and cool, 

 than when grown on a warm and dry 

 soil ; better on a moderately loose 

 and friable than on a hard, compact 

 soil. 



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