CULTURE OF THE GRAPE. 233 



commencing at Rochester, in New York, and extending 

 west along the shore of Lake Erie, and including its 

 islands, where the rain-fall does not average over nine 

 inches during the summer months; which is less than in 

 any other part of the Northern United States east of the 

 Mississippi. On Kelly's Island, in the western part of 

 Lake Erie, there is not only this favoring circumstance of 

 a light rain-fall, but also a remarkable freedom from dews 

 and fogs during the summer. After the water of the lake 

 becomes warm, the night temperature of the island is 

 kept up ; and the consequence is, that very little dew falls. 

 Fogs are also very seldom experienced. It is to this that 

 the cultivators on the island attribute their uniform 

 success in ripening their grapes, and their almost entire 

 freedom from mildew and rot. The water of the lake 

 preserves a uniformity of temperature, and prevents the 

 extremes of heat and cold. This alone is a most impor- 

 tant advantage, and a great safeguard against mildew. It 

 is a question, whether dew is in itself prouiotive of mil- 

 dew, or whether we should not, with more propriety, say 

 that the conditions which produce dew tend also to 

 develop mildew. This distinction is important; and I 

 confess that upon it my hope for the unprotected hori 

 zontal trellis to some extent depends. That such a trellis 



