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Selected Articles. 
its substance. Towards its root which is about half the size 
of the body of the sponge, the fibres are solid and of a dark 
red. It comes in strings packed in bales of different weights. 
Bahama Sponge. — This is found of two different forms ; first, 
in a rounded mass, surmounted by long mammillary projec- 
tions, giving it the appearance of a cow's udder ; second, that 
of a rounded mass, terminated by two curved surfaces which 
cross each other forming an angle in the middle of the sponge. 
The root is larger and of a dark red colour. This sponge 
has a smooth surface, its tissue is fine, but it wants tenacity. 
Sponges contain many extraneous substances, as fragments 
of stone, sand, broken madrepores and shells. Their fibres 
are also covered with a layer of animal matter of different 
degrees of consistence of colour, from all of which they must 
be freed before they are fit for use. 
To disembarras them from the sand, clay and animal 
coating, they are beaten and washed in large quantities of 
water, but to get rid of the other substance, they must be 
picked out by the hand if they are not soluble in weak hydro- 
chloric acid. Where those bodies are calcareous, they can 
be cleaned by placing them in earthen vessels and adding 
very diluted hydrochloric acid, after the impurities have dis- 
appeared the sponge must be well washed and then dried. 
Recently sulphurous acid has been employed instead of 
chlorine, for the purpose of bleaching them, this method has 
been very successful It is used only for the finer kinds, and 
does not injure their texture as much as the chlorine. 
Diet de V Industrie Manufacturiere, <^c. 
