456 BULLETIN OF THE BUREAU OF FISHERIES. 
whole being thoroughly stirred or tramped under foot to keep the heavier mate- 
rials in suspension and incorporate them in the texture of the sponge. At first 
. the excess of moisture was squeezed out by hand or with a clothes wringer, but 
later, when the desire for heavier loading became strong, the sponges were 
merely drained on a rack and then placed in the sun to dry. 
When the supply of sponges was temporarily increased through the intro- 
duction of the diving machine and the price fell, loading was almost abandoned 
and most of the goods were shipped pure. But during 1908 the practice again 
developed, though the loading did not exceed about 25 per cent. At the begin- 
ning of 1909, with an increase in the price, there was a tendency to increase the 
percentage. The sand, salt, and glucose which formed the bulk of the old load- 
ing have been replaced by barytes, epsom salts, and dextrin, which are less 
gritty, not so hygroscopic, and more readily worked out. The present desire to 
increase the loading will probably induce the use of sand, as it is difficult to get 
the added weight without it. 
Bleaching.—The sponges used in the arts are usually in their natural condi- 
tion so far as color is concerned, but for bath purposes many persons prefer them 
bleached. 
A fine whitish bleach which does not greatly injure the quality of the 
sponges may be imparted by repeatedly impregnating them with dense soap- 
suds and exposing them to the action of sun and air. 
A bright yellow color, such as is generally seen in the bath sponges of the 
shops, may be produced as follows: Soak the sponges for about ten minutes in 
5 per cent hydrochloric or sulphuric acid; then thoroughly wash in water and 
place in 5 per cent potassium permanganate solution until they have assumed a 
very dark brown, almost black, color; thoroughly wash again in fresh water and 
place, until almost decolorized, in a 10 per cent solution of oxalic acid. After 
another very thorough washing place them in a ro per cent solution of sodium 
carbonate (washing soda) until they assume a bright yellow color. A very 
thorough washing completes the process. The fiber of all chemically bleached 
sponges is more or less injured by the treatment, and though softer they are 
inferior to the natural sponges in durability and resiliency and soon become 
soggy in use. 
STATISTICS. 
No statistics of the Florida sponge fishery are available for years prior to 
1880, and no complete canvass, separate from the general fisheries of the state, 
was made until 1900. The following tables* exhibit in some detail the extent 
of the fishery in the years 1903 to 1908, inclusive, embracing the transition period 
during which hooking was largely supplanted by diving. 
@Compiled from a canvass made by Mr. John N. Cobb, Bureau of Fisheries. 
