22-1 D. Waldic-— 0;t tie Muddy Water of the Kufii. [No. 4, 



weaker still. It will be observed that my numbers differ widely from theirs. 

 The differences are to be accounted for, partly from the circumstance that my 

 examinations have been pushed further than theirs, thus shewing that one 

 lime salt is twice as efficacious as another, that some other salts are far more 

 powerful than lime salts, and that the salts of the heavy metals and particu- 

 larly of the sesquioxides seem to act on the same principle, which does not 

 appear to have been suspected by either Skey or Schloesing, at least is not 

 alluded to. It is also probably partly due to the differences of the mud 

 operated on, both as respects the composition of the insoluble matter it 

 chiefly consists of, as well as of the soluble matter that it may contain. 



V. — I had written thus far when I had an opportunity of seeing Schloes- 

 ing's paper in the original, in the Comptes Rendus, and found it much more 

 complete and interesting than I could have concluded from the brief ab- 

 stract in the Chemical News. He was first led to notice the peculiarity from 

 a circumstance I have mentioned before, namely the treatment of argillace- 

 ous soils with distilled water. He not only mentions that distilled water 

 rendered muddy by a mixture of purified fat clay is precipitated by l-l,000th 

 part of lime salts immediately, but that this is the case also by 1 -5,000th 

 part in some minutes and by l-50,000th part in two or three days. He 

 refers to the muddy water of the Seine becoming limpid in an hour or two 

 by a very small addition of a lime salt, but at the same time states that the 

 Seine water contains 89 milligrammes of lime per litre, equal to 8*9 parts in 

 100,000 or 15 '9 of Carbonate of Lime, a much larger quantity than that 

 which exists in the Hugli water during the rainy season, indeed nearly as 

 much as is found in December and January. Schloesing further directs 

 attention to the influence of this peculiarity on clay soils and on what is 

 called the mechanical analysis of soils ; and he further notices the precipita- 

 tion of mud so carried in rivers by the water of the sea, and also the practical 

 applications suggested by it for clearing muddy water. Indeed he concludes 

 by a reference to the waters of the Durance employed for supplying 

 Marseilles, tracing the muddiness of such waters to their sudden dilution 

 with large quantities of pure water and suggesting a remedy in the 

 restoration of the water to its normal condition by the addition of lime 

 salts or an admixture of some other water containing abundance of these ; 

 in complete accordance with all I have been contending for. Schloesing 

 states that Magnesia salts are about equally efficacious with Lime salts, and 

 that salts of Potash are required in about five times the quantity that 

 lime salts are, and that soda salts are still less active. He refers to no other 

 classes of salts, but speaks of Carbonic acid as producing the same effect, 

 attributing its efficacy to the solution of Carbonate of Lime present in the 

 insoluble state. 



This idea had occurred to myself, and that also it might explain the 



