48 
BRITISH ASSOCIATION.— 1835. 
nearly the same as that which he describes, in fact to be ulmin in an 
impure state. 
The specimen of turf to be bleached for paper is softened in cold 
water until its parts by agitation will separate ; the finer particles 
are washed off; the fibre which remains is digested in the cold w r ith 
a very dilute solution of caustic potass or soda, containing only 50 
grains of alkali to a quart of water. The solution, containing the 
geine in solution, is pressed from the fibres; the latter are then 
soaked for some time in very dilute sulphuric acid, consisting of 150 
grains of the sulphuric acid of commerce, in a quart of water. The 
iron is obtained in solution, and the ammonia if any exist in the turf. 
The fibre is now again separated by pressure from the dilute acid, 
and digested in the cold, w r ith dilute solution of chloride of lime, of 
the strength commonly used by paper-makers to bleach fine rags. 
After the bleaching has taken place the fibre is strained from the 
liquor, well washed, and applied to the manufacturer’s purposes. 
The extremely dark-coioured solution obtained by the caustic 
alkali is now treated with an excess of dilute sulphuric acid, and 
the acid of the previous washings may be in part used by the 
manufacturer for this purpose. The alkali is neutralized, and the 
geine precipitates. It is collected on a filter or by other suitable 
means, and well w r ashed with cold water, and finally dried by a 
steam bath, after which, if perfectly dried, it ceases to be soluble 
in water. It may now be used either in oils or distemper as a 
colour, being a rich brown bistre. 
The solution from which it has been separated contains sulphate 
of potass, and occasionally, in very minute quantity, sulphate of am¬ 
monia. 
The quantity of soluble matter in the turf operated on was found 
from 14 to 30 per cent.; and from one hundred weight of turf of 
proper quality may be obtained about 18 pounds of fine white fibre 
fit for paper-making, and a much larger proportion of a coarser and 
less white description. 
When the turf is digested in the chloride of lime, a thin film of 
an unctuous-looking matter floats after some time on the solution, 
and by careful management may be obtained in small quantity ; it 
appears to be a mixture of a gum resin with something analogous 
to wax, and of artificial camphor. 
This substance smells like common camphor. Its specific gravity 
is 0*990, which is a little more than that of camphor. It is at or¬ 
dinary temperatures always partly solid and partly fluid. When 
deprived of adhering water it shows a tendency to crystallize ; the * 
more fluid part gradually evaporates when it is exposed to air, and 
a varnish is left on the vessel which contained it. Its point of ho¬ 
mogeneous fusion is somewhere between 290 and 300 ; it evapo¬ 
rates rapidly between that and its boiling-point, which seems to be 
about 360. As it boils away, its boiling-point rises ; it is insoluble 
in water; a great part dissolves in alcohol, and the remainder is 
soluble in caustic potass and in fixed oils. 
