1960 The U K B G Guide to Drinks (3 rd edition revised)

Part Vn

SECTION I

MINERALS, CORDIALS, SYRUPS & SQUASHES

There are a considerable number of aerated waters some being naturally and the other artificially carbonated, or sparkling. The natural aerated waters, also known as mineral waters, contain some carbonic acid gas in solution as they issue forth from the soil; they may be drunk at the spring, in their sparkling condition, or else in any part of the world, after they have been bottled, in which case their carbonic acid gas is usually collected at the spring and the right quantity of it is then re-introduced into the water under pressure at the time of bottling : this is the only way to ensure that their degree of effervescence shall be exactly the same from bottle to bottle and from year to year. Aerated waters which are artificially carbonated are also called minerals: they are the more common and least expensive, but they contain none of the valuable mineral salts which many of the natural mineral waters contain, besides carbonic acid gas. The commonest of all artificially carbonated aerated waters are soda, potash and lithia waters, they are tasteless; other minerals such as'fizzy'lemonade and orangeade, are flavoured as weU as carbonated. The principle upon which car bonated waters are produced is that water absorbs under the normal pressure of the atmosphere about its own bulk of carbonic acid gas, and twice as much if pressure equal to that of two atmospheres be applied ; more as the pressure is increased. Carbonic acid gas is generated by chalk or whiting being treated with sulphuric acid; the gas thus obtained is stored in a gasometer,from which it passes into a condenser and eventually to the bottling machine. In the

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