Sxey.—Osomose, as the Cause of Suspension of Clay in Water, 485 
Lastly: I get a decided attraction (apparently) of camphor for camphor 
when this substance occupies the surface of water upon which it 
has rotated for a time sufficient to give a surface about half 
charged with the camphor compound, 
Art. LXXXII.—On Osomose, as the Cause of the persistent Suspension of 
Clay in Water. By Winam Srey, Analyst to the Geological Survey 
of New Zealand. 
[Read before the Wellington Philosophical Society, 9th November, 1878.) 
Tuar certain waters can and do persistently suspend clay is a fact which 
has been known from time immemorial, and the fact has also been known 
for a time nearly as long that when alum is added to water thus employed, 
the clay thereof is first coagulated, then precipitated, leaving the bulk of 
the water quite clear. This effect of alum has always been attributed to 
the fact that in a relatively large quantity of water it partially decomposes, 
producing a nearly insoluble basic salt which, as it precipitates, carries the 
clay down with it, entangled therewith, an effect which is therefore simply a 
mechanical one. In the year 1868, however, I showed* that the same 
effect could be produced chemically. I then brought under public notice 
the fact “that several neutral salts having their component parts so strongly 
combined among themselves as to render their decomposition by clay-water 
impossible, are individually capable of precipitating clay from suspension in 
water.” I further showed that such precipitates re-acquire a property of 
persistent diffusion, if well washed in pure water;+ and I then main- 
tained, and do still maintain, that these salts thus affect clay so suspended 
solely by the exercise of their affinities for water, by which means the clay 
is partially de-hydrated, and so has its density increased to such an extent 
that gravity soon markedly asserts its influence, causing the observed 
coagulation. 
* London Chemical News, No. 435. 
+ My claim as the discoverer of this effect of neutral salts has, to use a digger's 
phrase, been * jumped” by several investigators working independently of each other, 
but all, of course, in happy ignorance of the fact, that it was already properly “ pegged 
out.” One of these (Dr. Sterry Hunt, formerly of the Geological Survey of Canada), has 
even unconsciously followed me so closely and so far as to make the same damus of 
vus seem d this property of "h salts as I Pa ue to the explanation of 
tah 
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