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the first and second stages. I have also tried it with a 
known weight of perfectly pure sugar, and obtained almost 
absolute^ the theoretical amount of carbon. I hope to 
publish at an early date some of the analytical results 
obtained, and give at the same time comparative analyses by 
Wanklyn’s and Tidy’s methods. Until quite lately I have 
not been able to work out the process described above to a 
satisfactory termination. 
“ The Pollution of the Kiver Irwell and its Tributaries,” 
by Charles A. Burghardt, Ph.D. 
I have thought it would be interesting to the Members 
of this Society perhaps, if I laid before them the results of 
many analyses of the water of the Eiver Irwell extending 
over a period of two years, and also analyses of some of the 
most important tributaries of the Irwell above Manchester, 
including at the same time the Irk and the Medlock within 
the boundary of Manchester. There have been several 
investigations already into the condition of the Irwell, &c., 
the first being that of Lyon Playfair, in 1844. Undoubtedly 
at that time the river was extremely filthy, but I am quite 
certain from my own investigations, that it was inaccurate 
to state that large quantities of sulphuretted hydrogen, 
phosphor etted hydrogen, and other dangerous gases were 
evolved from the waters. Most certainly it could never 
have evolved phosphoretted hydrogen, because this gas can 
only be prepared by the reduction of phosphates under 
difficult chemical circumstances, which could not obtain in 
a river, but assuming for the sake of argument that this gas 
did succeed in forming after immense effort, and arrived in 
the shape of a bubble at the surface, if it consisted of the 
very inflammable modification, it would immediately take 
fire in the air, and burn at once to phosphorus pentoxide, 
and this latter body being one of the most hydroscopic 
