[May, 
258 The Ghost of the Season. 
matters could neither be detected chemically nor microscop- 
ically, and that the water was of the same quality as above 
the city. The report in full may be found in the “ Gesund- 
heits-Ingenieur,” a well-known German journal of samtaiy 
science. 
These investigations, I presume, had not come to the 
knowledge of the defunCt Commission in its land of 
shadows. 
From Silesia we turn to the State of Delaware. Professor 
A. R. Leeds, a chemist of well-known standing, has con- 
ducted very careful and prolonged experiments on the pollu- 
tions of the Passaic and the Brandywine Rivers. He 
concludes that “ there is no foundation in faCt for the oft- 
repeated statement that water once polluted by sewage cap 
never again become safe for drinking purposes.” In addi- . 
tion to the aCtion of the atmosphere and of water-plants, he 
points out that the finely-divided earth washed into the livei 
by. rains occludes and precipitates the impurities. The 
Passaic river, it appears, is pure down to the town of Pater- 
son, where it is polluted by the sewage and manufacturing 
refuse. Yet 16 miles lower down it returns to a condition 
of purity little inferior to what it exhibits above Paterson, 
and serves as a water-supply for the 300,000 inhabitants of 
Jersey City and Newark. Dr. Leeds writes : — “ The river 
immediately below the town is black with dye-waies ; the 
fish carried over the Falls are immediately poisoned, and I 
have often seen the foul-smelling and disgusting watei 
covered with their floating carcases. \ et samples taken 
at intervals of a mile apart down the river show a regular 
diminution in the organic nitrogen, and. a disappearance of 
the nitrites. To give the aCtual figures, just above Paterson 
the albumenoid ammonia was found to be o'oi6 grain per 
gallon ; below Paterson it had risen to o‘o68 grain ; whilst 
at Broadway Bridge it had sunk to 0*024, at Dundee 
Dam to 0*018 grain per gallon. Thus the gradual oxidation 
and disappearance of the organic matter is distinctly shown. 
A full account of the observations and experiments of Prof. 
Leeds may be seen in the “ Annual Report of the Chief 
Engineer for the Water Department to the City of Wil- 
mington, Delaware, for the Year 1882” (Wilmington : James 
and Webb), and “ Pollution of the Passaic River ” (Newark : 
Inglis and Co.) ; or see “ Chemical News, Maich 3 ®^L and 
June 22nd, 1883 (pp. 153 and 292). 
A third case may also be noticed. The River Vesle, above 
the town of Rheims, is fairly pure. It is severely polluted 
on its passage through Rheims, which has been called the 
