242 Alcoholic Fermentation in Cider. [july, 



various sources, many: for example being found attached to the 

 skins of apples and being washed off into the juice at the time 

 of grinding and pressing the fruit, while some are always pre- 

 sent in the atmosphere of cider-making premises and attached 

 to the appliances used for cider-making. • - 



Yeast, though called a germ, is an exceedingly minute plant. 

 In structure it is one of the simplest members of the plant 

 kingdom, each individual consisting only of a small globular 

 mass of living matter, surrounded by a protective covering or 

 wall, such a structure being termed a cell. Higher forms of 

 plant life, eg.^ apples, consist of a very large number of cells 

 grouped together to form the tissues or the body, but the yeast 



Figures showing Multiplication of Yeast Plants — 

 By Budding, i, 2; and Spore Formation, 3, 4. 



plant consists of a single cell only. Its size is so small, that 

 thousands can be contained in a small drop of water. Its 

 method of growth or multiplication is also simple. At some 

 point of the cell a small protuberance begins to develop, which 

 gradually increases in size and assumes a roundish shape, until 

 it at length is almost as large as the parent cell, which it entirely 

 resembles. During this period the parent and daughter cell 

 have remained attached to and in communication with one 

 another at the point where the latter first appeared, but later 

 they separate from one another, two adult plants exactly the 

 same in character as the original one thus being produced. This 

 process is known as " budding," and may be compared to the 



