376 AMERICAN GRAPE CULTURE. 



some men are constitutionally more liable to 

 disease than others, so some kinds of vines are 

 constitutionally more liable to disease than 

 others. There are conditions which favor, or 

 even invite, the attacks of disease in men ; and 

 it is the same with the vine. All kinds of 

 vines, no matter what their constitution may be 

 are liable to disease, if placed under conditions 

 favorable to its attacks ; there is not a variety in 

 cultivation that has proved an exception, and 

 there never will be. When, therefore, it is said 

 that a vine is healthy, it is in the sense that we 

 say a man is healthy when he is not subject to 

 constitutional disease ; at least, that is the sense 

 in which we use the term. What we wish 

 the reader to understand is simply this : that 

 all kinds are liable to disease, some more 

 and others less; and that all kinds, without ex- 

 ception, if placed under conditions unfavorable 

 to the healthy action of the leaves or roots, will 

 become enfeebled or diseased. He will then ap- 

 preciate the importance of studying the condi- 

 tions which are necessary to health or strength, 

 and endeavor to supply and maintain them ; he 

 will understand that the health of the vine is 

 in a great measure under his control, and that 

 he can judge of the hardiness of kinds only by 



