1867.] Chemist)'!/. 529 



fessor Wanklyn's table winch gives the results in " parts in 

 1,000,000, i.e. milligrammes in a litre," there is in — 



Description of Water. 



Ammonia, as such 

 and as urea. 



Albumenoid am- 

 monia. 



Water from Bala Lake 



Locli Katrine, from main in Glasgow 

 Woodhead water supplied to Manchester 

 Thames water supplied to London hy "West 1 



Middlesex Company / 



New River 



o-oi 



0-02 

 001 



0-01 



0-01 



0-25 

 013 

 0-07 



0-064 



0-05 



These results, it will he seen, differ very widely from those of 

 Dr. Frankland, and the whole subject seems to require further 

 investigation. The process by which Professor Wanklyn obtains 

 the albumenoid ammonia will be found in the abstract of his paper. 



While on this subject we may quote the directions given by J. 

 Loewe for the separation of organic matters from a water.'* 



In the first place the water is boiled until all carbonic acid is 

 expelled. Any deposit is then collected, washed, and boiled with 

 distilled water, adding at long intervals crystallized chloride of 

 ammonium as long as any odour of ammonia is given off. A 

 solution of acetate of copper is then added as long as a precipitate 

 is produced. This precipitate is decomposed by sulphuretted hydro- 

 gen, and the filtered solution is evaporated to dryness on a water- 

 bath. The author has only obtained traces of organic matter in 

 this way. The water separated from the precipitate produced by 

 boiling is now concentrated, and when cold, acetate of lead is added. 

 The precipitate is first washed with boiling water to remove chloride 

 of lead, and then with hyposulphite of soda to remove sulphate; 

 there then remains only the organic compound of lead. To secure 

 all the organic matter the liquor decanted from the acetate of lead 

 precipitate must be treated with sub-acetate of lead; this second 

 precipitate will, besides the organic compound, contain oxy-chloride 

 and sub-nitrate of lead. These being got rid of, the mixed lead 

 precipitates are decomposed by sulphuretted hydrogen, and the solu- 

 tion is filtered and evaporated. It is said that the residual organic 

 matter obtained by the author was free from nitrogen ; but we are 

 not told what water he examined. 



W. Heintzf gives a method of determining the amount of 

 solids, both organic and inorganic, which does not much differ from 

 that usually employed by careful chemists. The author evaporates 

 below 100° C. sufficient water to leave from 0*3 to 0*6 gramme of 



* ' Zeitschrift fiir Chemie.' New Series, V. ii., p. 595 ; and ' Bulletin de la 

 Societe Chimique de Paris,' June, 1867, p. 497. 



f ' Zeitschrift fur Chemie.' New Series, V. ii., p. 586. 



