DUFOUR'S ACCOUNT OF THE DISEASES 93 



earliest accounts of this mischievous disorder is John- 

 son's, in 1806, although his entire discussion of it is 

 as follows: "The Mildew sometimes attacks the grapes 

 and fruit, when the vine has been planted in too wet 

 a situation, or when the weeds are suffered to prevail, 

 but never when the vineyard has a gentle declivity." 

 The first explicit account of the vine diseases which 

 I know was made twenty years later. "The different 

 diseases that I have seen afflicting vines are not nu- 

 merous," writes John James Dufour, in 1826. "They 

 may be denominated, 1st. the Mildew, called Charbon 

 or Tache, by the French, whose meaning is, by Char- 

 bon, burnt to a coal, or like a coal; and by Tache, a 

 black speck: 2d. Unripeness of the young wood, 

 which causes it to be frostbitten: 3rd. Short jointed, 

 called Sorbatzi, by the Swizzers: 4th. Exhaustion, 

 by overbearing." Only one of these classes, the mil- 

 dew, need attract our attention at this time. Dufour 

 describes it as follows: "The Mildew, or Charbon, is 

 the most severe disease that sickeneth grapevines. 

 One of the first symptoms is a mouldy and black dust 

 that appears some time on the under surface of the 

 leaves in the months of July and August, and grows 

 gradually more intense. Black specks then appear on 

 the young parts of the shoots, and on the fruit, as if 

 made with a hot bit of iron : the leaves then crisp and 

 fall, the fruit becomes black, and dries, and what fruit 

 seems to escape the sickness, will not ripen well, and 

 remain uncommonly sour; the young shoots will be 

 extremely brittle, and the pith black." It is very likely 

 that two diseases are confounded in this descrip- 

 tion. The account of the leaves suggests the downy 

 mildew; but the description of the affected shoots and 



