Rum is a by-product of the sugar industry, and "mescal" is distilled from the agave.
It was about this time that the first experiments were made (in Germany) with basic slag, a material which had hitherto been regarded as a worthless by-product of steel manufacture.
This is generally effected by adding the calculated amount of potassium chloride (of which immense quantities are obtained as a by-product in the Stassfurt salt industry) dissolved in hot water to a saturated boiling solution of sodium nitrate; the common salt, which separates on boiling down the solution, is removed from the hot solution, and on cooling the potassium nitrate crystallizes out and is separated and dried.
Of this increase, a considerable part was derived from gold-quartz mining, though much was also obtained as a by-product in the working of the ores of other metals.
Some attention is also being given to the manufacture of alcohol for power purposes in Hawaii, Porto Rico and the Philippines; and in Cuba, from the molasses produced as a by-product in the sugar refineries.