PRESERVATION OP FISHERY PRODUCTS FOR FOOD. 
559 
It is claimed that the cost of utensils required for the preservation of lish accord- 
ing to the above process amounts in this country to about |30, the cost of a cask 
being $30 and of a pump $10. The cask should be made of stout steel, and capable 
of containing 200 or 300 pounds of fish. The utensils should last five years, and one 
inimp is sufficient for a large number t)f casks. If the cost of materials be distributed 
over five years, the average cost will be $6 iier year, so that in case the cask is filled 
only once a year the cost of utensils and materials is a trifle over 2 cents per pound of 
fish. But as each cask may be filled twenty times a year, and one pumi> will suffice 
for a large number of casks, the cost is reduced to one-tenth of 1 cent iier pound. 
The following extract is from an article in the Fish Trades Gazette, of London, 
July 31, 1886: 
The Roosen i)rooeas is now pretty well known in England, and it is generally accepted as being 
far the most successful attemjit to keep lish not only fresh, hut also sweet, wholesome, and attractive 
for long periods. The process, it may he added, is not confined to fish, hut has been applied with 
equal success to meat, game, fruit, etc. Exjjeriments have been carried out in Scotland, and public 
demonstrations of the value of the process made in Edinburgh and Glasgow, where its merits have been 
recognized by the very highest authorities on the subjects of fishing and the fish trade. Messrs. 
Dufresne &, Luders, the agents of Mr. August R. Roosen, of Hamburg, the inventor of the process, 
lately decided that it would be well to make the process better known in Loudon, and accordingly 
invited a number of rejiresentative guests to witness the opening of several casks of fish preserved 
by the Roosen jn’oeess and to taste the same when cooked. There was an excellent resjionse to the 
invitation, the guests including many famous authorities in science and in medicine, as well as others 
holding important governmental positions or being connected with commerce, not only in England, but 
also in the colonies and Indian Empire. Two casks, which had been closed for seventeen days, were 
opened before the comiiauy, and the fish when taken out were found to be perfectly sweet and fresh, 
bright-looking, and as attractive as the day they were caught. On being eaten they were pronounced 
excellent, and the advantages of the process were highly commended. 
A process somewhat similar to that introduced by Eooseu was devised* by 
Magnus Gross, of Washington, D. 0., in 1859. Gross’s method diftered from Eoosen’s 
in employing hydrostatic pressure instead of a force pump and in using a strong 
solution of common salt (100 pounds) mixed with carbonate of soda (4 pounds) and 
carbonate of potash (2 pounds). This method was intended for the preparation of 
salted fish, the product being packed in dry salt after the curing iirocess, and it was 
never used to any commercial extent. 
ECKHART PROCESS. 
In 1877 John Eckhart, of Munich, -Germany, patented t a proeess of preserving 
fish and meats by introducing a solution of salicylic acid with an apparatus similar to 
that used in the Koosen iirocess for preserving fresh fish. The solution was made by 
dissolving half a pound of salicylic acid in 100 iiounds of water. A hydraulic pressure 
of 12 atmosiiheres was afiplied for from one to two hours. In 1882 Eckhart introduced 
another antiseptic compound J for fish, salt, boracic acid, tartaric acid, and salicylic 
acid being used instead of boracic acid alone. The mixture was composed of 50 per 
cent salt, 474 per cent boracic acid, 2 per cent tartaric acid, and 4 per cent salieylic 
acid. In its application the fish are stripped of skin and bones and mixed with the 
compound in the proportion of 2 pounds antiseptic to 100 pounds of fish. They are 
next packed in cases of animal tissue or parchment and put into casks filled with a 
gelatin solution made in the proportion of 10 pounds of gelatin, 4 pounds of the anti- 
* Letters Patent No. 26427, December 13, 1859. 
t Letters Patent No. 194.5.50, August 28, 1877. 
t Letters Patent No. 251772, January 3, 1882. 
