I 



on Glycerate of Potash. 439 



In order to decide this question, the following experiments 

 were made : — 



Glycei-ate of baryta was boiled with a concentrated solution of 

 caustic baryta for several hours. On examination of the liquid, 

 the substances employed did not appear to have undergone any 

 perceptible change. 25 grms. of glycerate of potash were dis- 

 solved in a solution consisting of 25 grms. of caustic potash 

 and 50 grms. of water, and the liquid evaporated at a high tem- 

 perature until a small portion of it, after neutralization with 

 acetic acid, gave a white precipitate on the addition of acetate of 

 lead. The residue, which assumed the consistency of glycerine 

 or strong syrup, as soon as it became cold was dissolved in water 

 slightly acidulated with acetic acid, and acetate of lead added 

 as long as a precipitate was formed. The examination of the 

 filtrate from this precipitate will be described presently. 



The lead precipitate^ well" washed, was mixed with water and 

 decomposed by sulphuretted hydrogen. 



The solution separated from the sulphuret of lead gave, on 

 evaporation, only crystals resembliiig oxalic acid. The latter 

 dissolved easily in water, and produced in a solution of sulphate 

 of lime a white precipitate, insoluble in an excess of acetic acid. 

 With sulphuric acid the well-known reaction of oxalic acid was 

 obtained. Some of the crystals, dissolved in water, neutralized 

 with annnonia, and added to chloride of calcium, gave a white 

 precipitate, which was well w^ashed and dried at 100^ C. 



0-619 grm. of the substance thus obtained yielded, according 

 to the usual method, 0'-i39 grm. of carbonate of lime. If it be 

 supposed that the precipitate wasoxalate of lime(C-Ca-0'*+II~0), 

 0-441. grm. of carbonate of lime ought to have been obtained. 



The liquid from which the oxalate of lead had been precipi- 

 tated was freed from lead by means of sulphuretted hydrogen, 

 evaporated on the water-bath to the consistency of syrup, and 

 mixed with as much dilute sulphuric acid as was necessary to 

 saturate the potash which it contained. 



Three times its volume of strong alcohol was now added, and 

 the whole allov.ed to stand for some hours. The sulphate of 

 potash which had separated was collected on a filter, washed with 

 s])irits of wine, and the alcohol distilled off from the filtrate. To 

 remove the last traces of sulphate of potash from the acid residue 

 left in the retort, it was mixed with absolute alcohol, filtered, 

 and the filtrate again distilled. The retort contained an acid 

 licjuid, which was diluted with water, and neutralized with car- 

 bonate of lime at 100^ C. After filtering off from a little sul- 

 phate and carbonate of lime, the li([uid was concentrated by 

 eva|)oratiou and left to stand. A large quantity of crystals, 

 of the upjjcarancc; of lactate of U>ue, separated. The latter were. 



