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planted shallower, have roots that do not absorb 

 moisture so fast as the others, or have a power in 

 their leaves to transpire it more freely. 



Professor Lindley, remarking upon this disease, 

 observes, that when a plant remains in a healthy state, 

 but its leaves are excessively distended with watery 

 matter, the first thing that happens is an increase in 

 size, or number, or perhaps in both, of the green blad- 

 ders that lie between the veins of the leaves, and 

 which, growing faster than the veins that bound them, 

 form, as Mr. Johnson has stated, excrescences and ex- 

 pansions, presenting the appearance of blisters. This 

 happens continually, in vineries, to vines growing with 

 great vigour, whose leaves will then present innumer- 

 able green bags, or bladders, springing up from their 

 surface and deforming them. 



The disease of the vine-leaf in a vinery is of the 

 same nature as the bhster of the peach-leaf in front 

 of a south wall. There is no essential difference be- 

 tween them ; it is only one of degree, that of the 

 peach being the more severe. In both instances the 

 cause is the same ; namely, the accumulation in the 

 leaves of watery matter derived from the soil. If this 

 be so, it can hardly be said tbat cold is the primary 

 cause of the mischief; for no cold is experienced in 

 those vineries where the malady is the most conspicu- 

 ous. We do not, however, entirely deny the evil influ- 

 ence of low temperature. It is very possible that it 



