CON CENTRA′TION

The volatilisation of part of a liquid in order to increase the strength of the remainder. The operation can only be performed on solutions of substances of greater fixity than the menstrua in which they are di olved. Many of the liquid acids, solutions of the alkalies, ., are concentrated by distilling off their water. In pharmacy , the term CONCENTRATED is commonly applied to any liquid preparation po e ing more than the usual strength. Thus, we have concentrated infusions, decoctions, liquors, solutions, tinctures, and e ences, most of which are made of 8 times the common strength. This is generally effected by using 8 times the usual quantity of the ingredients, with a given portion of the menstruum, and operating by digestion and percolation; the latter being generally adopted when the articles are bulky. When the menstruum is water, a little spirit is added, to make the product keep. See Decoction , Infusion , .