OCR Text |
Show 50 PRICKLY SALTWORT. in astate of purity. In called potash; far, however, frombeing this state it occurs in commerce. state, except in wells in It is seldom found in an uncombined exist in the aluminous to said towns, as at Douay, &c. It is ore of La Tolfa. , and In combination with the sulphuric, nitric andin the East Indies. muriatic acids, it is found in Spain, the vegetable alkali, but ted mina deno rly Potash was forme dantly in mineral bodies, improperly, becauseit is met with abun Dr. Kennedy haslately more especially in volcanic products. uelin has found it in discovered it in the pumice stone. Vauq has likewise disroth the zeolite from the Ferro islands. Klap genus. eous silic covered it in the Jeucite, au earth of the potash be deher whet ed agre Vegetable physiologists are not grow; whether it exists rived from the soil in which vegetables her it be a product of uncombined with any acidin plants ; whet ng the process of duri d rate gene be it vegetation ; or whether burning. its pure state, bePotash was for a long time unknownin examine its propercause it was difficult to obtain it. We shall methods of obtaining it. ties in that state, and thenpoint out the Prorerties oF PoTasH. of soft quadrangular Potash, in a crystallized form, consists c and deliquescent. compressed prisms, which are extremely causti when brought into contact It dissolves all soft animal matters rises in fumes at high with it. It liquefies by a gentle heat, and manner with phosdirect temperatures. It does not unite in a ur and metallic oxides. phorus. It easily combines with sulph even a small quantity and way, [t dissolves alumine in the humid zircon, nor on magor e glucin on act of silex; but it does not barytes. It absorbs nesia or lime. It contracts no union with with silex water and carbonic acid rapidly. It fuses into glass not yield do l genera in which salts forms It by the aidof fire. colours ble vegeta blue their acid unless to barytes. It changes es. alkali of green, and possessesall the general properties Mernops of ostatnine PorasH. chemists to possess @ me It has long been a desideratum with purity ; the strong thod of preparing potash in astate of absolute ely dif tendency which it has to combination renders this extrem :— of use made now ficult. The following are the methods PRICKLY SALTWORT. 251 a1, v Bouillon Pinasall V eange’sapparatus ar 5 ‘ la Grange’s * consists of several boxes of common deal. At the bottom put river sand, which must be é add another stratum, but of afiner well washed, and over it kind, and cover the whole with a cloth, besprinkied with wood ashes. In the bottom of each box a hole is made, into which affordi “nose of affording fitted a glass tube, for a passage to the purpose for the glass tube, iss fitted the liquoras it filters through the sand. Having arranged the apparatus in this manner, take equal parts of quicklime and potash of commerce, if the lime is very caustic; but in the contrary case, it requires twenty parts of . ] for int ach Ya) 1 ime to fifteen lime ofP potash: put+ water into an ‘iron kettle, bring it nearly to a state of ebullition, and then add lime, which by its slaking will bring the water to that state completely. When it is slaked mix {he potash, and form of the whole a thickli. a nla i ES 5 : ‘ ae ° o 5 ; . . quid, which must be suffered to cool a little. Then pourthe mixttee mta ay * * © mixture into the the boxes, and immediately throw water overit; but to prevent the water from making holes, when added, place over it a small board, which will rise with the water. ‘are must must be take to place a earthen pans, or othervessels, Care be taken i eval et hat re lic . iC r to receive the liquor which runs through the tubes; and, that the ley may not absorb carbonic acid from the atmosphere, 4 the I z . 1 eeale mck } vessels must be closed with care, in such a manner as to exclude the€ ut external {t will will be sag r also to keep water always rnal air air. It be necessary over the mixture, which must be collected till it passes tasteless from the tubes. pans liquors obtained are nearlyof the same degree of strength l towards the end of the process, when they grow weak suddenly. Pee en eae : . é : Lo. evaporate the water, use should be madeof cast iron pots, eomni 7 : Rohe : ; ginning with the last portion, which are alittle weaker; and to prevent prevent the tl necessity ecessity of of keeping keepi i the strongest a long time in contact wit! the» air air when whe boiling, iting a strong ebullition Spullition’is requii act with oe e. site. a 1 ro } ; ¢ ar e : degree, any re concentrated to a certain Whe theSPA When fluid is } : ae may be present will potas} that lize, and be sulphat crystal phatee of of potash 7 ee precipitated. 3 : Peth pour the concentrated liquor we potas obtai dry into a To obtain small bason, be ‘ : till a little of it small and proceed with the evapoi ' ; ees Oure on Dna Poured an iron plate, or a marble slab, becomes solid. La Grange’s Manual of Chemistry, vol. i. p. 172. |