GENUS INNUMERABLE VARIETIES. 349 



duced by the addition of sugar, in which it remains 

 in an undecomposed state ; but no sooner is the 

 temperature of the liquor increased by removal into 

 a warmer atmosphere or otherwise, than the vinous 

 fermentation goes on, disengaging, of course, con- 

 siderable portions of carbonic acid gas. 



Naturalists have arranged, not only the APPLE, the 

 PEAR, and the QUINCE, under the genus Pyrus or 

 the PEAR, but also many other species, to the num- 

 ber of twenty or more, of which it is not necessary 

 to name any other here, except those just mentioned ; 

 and the Pyrus prunifolia or SIBERIAN CRAB, a small 

 apple now well known in many of our gardens, a 

 native of Siberia. 



The origin of all our apple, as well as pear trees, 

 appears to be the wild crab tree, and the wild pear 

 tree, both found wild in various parts of Europe, 

 and also in this country. But that which is very 

 remarkable, the wild variety of the APPLE, Pyrus 

 malus, and of the PEAR, Pyrus communis, is armed 

 with thorns. The innumerable varieties, both of 

 apples and pears, now found in this country, and 

 other parts of Europe, have been from time to time 

 obtained by domestication of the wild trees, and by 

 sowing the seeds, by which continual new and valu- 

 able varieties are produced. Such, indeed, is the 

 number of varieties now to be obtained both of apples 

 and pears, that whoever desires to rear apple and 

 pear trees, must make a selection from the number 5 

 it is scarcely possible in a moderate-sized orchard, 

 that he should be able to rear the whole : for we 

 find on referring to London s Encyclopedia of Gar- 



