Such brine, although repeatedly used, will not putrify, nor the fish, if kept under the surface, become rancid. By this process great quantities of herrings may be salted when salt or casks are not on the spot, and the fish may remain for a great length of time immersed in this brine without the least injury. From Mr. London’s statement, it appears that the brine ought always to contain a redundancy of salt; and in such case there is not the least danger of the fish putrifying or growing rancid, as the extra lumps of solid salt in the brine immediately act upon any watery or other liquors which proceed from the fish when inclosed in the cask. For judging of the relative strength of different solutions of common salt, Mr. London recommends a glass bottle, with a ground-glass stopper, to be filled with brine made from a solution of solid salt in water; within this bottle are three glass bubbles, of different specific gravities, so graduated, that supposing the temperature of the air to be at sixty degrees of Fahrenheit’s thermometer, and only one bubble floats on the surface, and that it indicates the specific gravity of the brine to be 1.155, containing about 20 parts salt, and 80 of water, which is insufficient to cure animal matters with certainty by immersion in it. When the second bubble floats, it indicates the specific gravity of the brine to be 1.180, or about 24 parts salt, and 76 parts water, which may be used for the purpose of immersion. This brine will fully answer the purpose in the hottest weather in most climates, provided the meat or fish is always completely covered with the brine. PICKLED MACKEREL. After splitting the fish, and having taken off their heads and part of the skin of the belly, let them be laid in brine about three or four hours; then put them in jars with the following pickle:--two pounds common salt, two ounces saltpetre, one ounce of sugar, half ounce white pepper, one drachm corriander seed, pounded all well together; sprinkle with this mixture the bottom of the jar; then put on a layer of mackerel, with the back downwards; then a layer of the spices, and then another of mackerel, alternately, till the jar is full; press them down, and cover them close. In six months they will be ready for use. PICKLED SALMON. Split the fish down the middle, and divide each half into six pieces. Make a brine of salt sufficient in quantity to cover the fish when placed in a saucepan. Season with bruised pepper, mace, and allspice, and simmer the whole till the fish is done, taking care not to boil the fish more than is barely sufficient. Then take out the pieces to cool, and put them into a jar. Strain off the spice from the liquor in which the fish was boiled, and add to it a like quantity, by measure, of vinegar, and pour it over the fish. When cold, tie it over with paper, and keep the fish submersed under the liquor, by placing a weight on it. COLLARED EELS.