FISHERY INDUSTRIES OF THE UNITED STATES. 21 
Standards is continuing its mvestigations of the characteristics and 
qualities of these leathers. One sample of shark leather possessed a 
tensile strength in excess of 6,500 pounds per square inch exceeding 
that of calfskin tested. Wearing tests of shoes are also being made. 
For this purpose 14 pairs of shoes, one shoe of each pair of shark 
leather and its mate of calfskin; seven pairs of shoes, one of porpoise 
and mate of side leather; and two pairs of shoes, one shoe of whale 
leather and mate of calfskin, are being used. It is assured that 
leather of good quality can be made from shark hides, and ready mar- 
kets thus far have been found for good grades. There is need for 
more attention to the subject of quantity-production, to the trial of 
small, easily movable reduction plants to care for the oil, scrap, and 
fins, and to developing the interest of fishermen to save and utilize 
their catch of sharks. A report is being prepared covering the 
investigations in this field. 
SHARK FINS. 
There is an apparent demand for a much larger supply of dried 
shark fins. San Francisco is the center of the industry in the United 
States, the receipts at that port amounting to about 5 tons per 
month. Much the larger portion is imported from the west coast of 
Mexico, the balance being received from California points and a few 
shipments from the Atlantic coast. The Chinese merchants are the 
largest buyers and export the bulk of the material to China, the 
balance being absorbed by the local trade. 
Unlike conditions in the principal oriental markets, very little 
distinction as to the species of sharks from which the fins are taken is 
made, provided the fins are of good size, properly trimmed and cured. 
The fin should be cut off at the body, with all fleshy parts trimmed 
off, leaving only the true fin. The marketable fins are the dorsal on 
the back, the pectorals or anterior paired fins, and the anal. The 
large dorsal is preferred, while the caudal or tail is worthless. The 
fins must be at least 6 inches long, and those ranging from 8 to 14 
inches are preferred. 
for curing the fins should be thoroughly dried in the sun without 
salt or other treatment, then packed, preferably in cases or barrels 
weighing about 250 pounds, or put up in sacks to weigh 150 or 200 
pounds. Choice grades haye commanded as high as 65 to 75 cents 
per pound, but fins badly cured, improperly trimmed, etc., command 
much less. 
PEARL ESSENCE OR FISH SCALE ESSENCE. 
The art of using the silvery pigment from fish scales for ornamental 
purposes is said to have been discovered by the Chinese. In 1680 
artificial pearls were first made in western Europe by Jacquin, a 
rosary maker in Paris, and the trade has been largely conducted in 
France, Germany, and Italy. The silvery coating of the scales of 
certain fishes, freed from organic matter and eomposed of minute, 
oblong bodies which en masse under suitable conditions supply an 
iridescent effect, is employed for the purpose. This material is 
known as essence d’orient, pearl essence, or fish-scale essence. In 
the manufacture of the artificial pearls the inner wall of the thin 
