In curd soaps, however, which form the basis of most household soap, the uncombined alkali and the glycerin are separated by " salting out, " and the soap in this condition contains about 30% of water.
Then without further addition of alkali the boiling is continued for a few minutes, when the soap is ready for salting out or " graining."
There is no separation of underlyes in potash soap, consequently the product contains the whole constituents of the oils used, as the operation of salting out is quite impracticable owing to the double decomposition which results from the action of salt, producing thereby a hard principally soda soap with formation of potassium chloride.
Imports include coal,timber, tar and hemp. Steam sawing, metal-founding, fish-salting, shipbuilding and repairing, and the manufacture of ship's-biscuits and fishing-nets are among the industries.
==Agriculture and other Industries== The cultivation of rice, which is grown mainly in the small deltas along the coast and in some districts gives two crops annually, and fishing, together with fish-salting and the preparation of nuoc-mam, a sauce made from decaying fish, constitute the chief industries of Annam.
Among other things Hales invented a "sea-gauge" for sounding, and processes for distilling fresh from sea water, for preserving corn from weevils by fumigation with brimstone, and for salting animals whole by passing brine into their arteries.
One explanation has been sought in the legend of St Nicholas miraculously restoring to life three rich youths, who had been murdered, cut up and concealed in a salting tub by a thievish innkeeper or butcher, in whose house they had taken lodging.
The value of the herring fisheries is enhanced by the careful methods of smoking and salting, the export of salted fish being considerable.
The salting and curing of the fish is done chiefly at Mataria, on Lake Menzala, and at Damietta.
In Burma the favourite relish of nga-pi is prepared from fish; and at Goalanda, at the junction of the Brahmaputra with the Ganges, and along the Madras coast many establishments exist for salting fish in bond.
In medieval times the salting and sale of herrings and the sale of cod, fish and other products of the North Sea fishery were the only industries.
Apart from the cattle driven into the mining districts for consumption, a number of saladeros are employed in preparing (usually salting and sun-drying) beef for the home markets.