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116 which is obtained by exposure to the sun in summer, or from stoves in cold weather. But from exposure alone acidity would take place in time without any artificial heat being applied.

We are now treating of vinegar made from malt without reference to that made on the Continent from grapes or wine; but heat we believe is also had recourse to there to accelerate the same process. The vinous fermentation, in vinegar made from every vegetable matter, must, to a certain extent, precede what is called the acetous, as it is alcohol only which imbibes oxygen, and becomes acetic acid.

Chemists inform us that the acetous fermentation may set in during the fermentation of beer, after it exceeds a certain temperature in the gyle-tun; but they cannot afford any chemical proof of this statement. We have seen beer, the fermentation of which was begun at 80° F., and carried to upwards of 90°, and which beer at the end of twelve months bore the test of litmus paper as well as any Bavarian beer that has been met with by us, and this notwithstanding that the latter beer had never exceeded perhaps little more than half that temperature in its fermentation. It is proper, however, to add, that the former beer, as well as all the Bavarian beer which I have seen, wanted vinosity, and had a mawkishness in flavour which would not generally please in this country.