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Rh yeast plant of beer Torula cerevisicœ; he considers each infusion to have its peculiar plant, and he names the whole race of such beings Levurians. No doubt the yeast of beer consists of minute molecular matter, the particles of which are globular, and that those particles produce from their sides, other particles like themselves, which eventually separate from the parent, but we do not know that they are therefore plants.

Before the experiments of Mr. Brand, alcohol was by many supposed to be a product of distillation, and not of fermentation. He has, however, satisfactorily proved its existence in the fermented wash, by producing it already formed from that fluid without distillation.

Other chemists have ventured to declare, that they have discovered living animalculæ in yeast. I here insert Professor Liebeg’s opinion upon these subjects.

“The fermentation of sugar,” says Professor Liebeg, “in contact with yeast, is quite distinct from that of a vegetable juice, or of wort of malt; in the ﬁrst case, the yeast disappears with the sugar, Whilst in the second instance, it is formed during the metamorphosis which the sugar undergoes.

“The form and the nature of these insoluble