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growth, so sliallow as to suffer from drouth, or so impermeable a little distance from 

 tlie surface, that the rootlets will remain immersed in wetness in consequence of the 

 falling water not passing off freely, are among the most common terrestrial predi^pos- 

 ing causes that operate after the vines have become Avell established in bearing as well 

 as during their preparatory growth. That of covering the vines too deeply in plantinfj- 

 must not be unnoticed, for it is one of the most frequent occurrence, and disastrous in 

 its effects. Covering too lightly may be equally injurious. 



Among the most common aerial predisposing causes, are the crowded state of the 

 leaves, by which one overshadows another, and prevents full exposure to the action 

 of the sun. This comes from suffering the canes to grow too near together, or too 

 long, or from permitting the laterals to become too long before being removed. 



The same is produced by' training the vines too closely to a sheltering wall or 

 building — by proximity of trees or hedges, and by placing the lines of trellis too near 

 each other. A confined place deprived of moving atmosphere, and a bleak place 

 greatly exposed without shelter on any side, are about equally objectionable. A rad- 

 ical defect at the beginning has always existed to a very great extent from using 

 defective plants, that bring the inevitable predisposition with them. This was a lead- 

 ing cause of failure less prompt than at present before the oidium of Tucker appeared. 



The exciting causes, besides general low temperature and excessive rain, are 

 changes of the atmosphere from favorable to unfavorable conditions, often sudden, 

 severe, and long-continued, by which, as before stated, the texture of the epidermis is 

 softened and covered with the adhesive exudation that favors the lodgment and germi- 

 nation of the spores ; but the weather also favors the deposit of moisture, and brings the 

 scarcity of light that favors the parasitic germination. It is believed that the sporules 

 of some of the parasitic fungi are taken up by the stomata of the roots with the plant 

 food ; and from that it has been argued that the same occurs, also, with the OYdium 

 Tuckeri in the grape; but careful and extensive microscopic examinations have shown 

 that this does not take place. 



It should be stated that in Europe, while the oidium was involving all of the 

 vines in great damage or destruction, the American vines, Isabella and Catawba, by 

 their side, were not affected, showing their greater abilit}'- to resist the predisposing or ex- 

 citing causes, or perhaps both. The European vinej-ards for many years were rendered 

 so unproductive, that wine advanced several fold in price, and a little progress was made 

 in introducing American grapes for its production. The Isabella was chosen for that 

 purpose, but from the " badness of the quality," in consequence particularly of its 

 offensive. odor and flavor, it was not planted to much extent. The use of sulphur and 

 improved management have happily restored the European vineyards to health and 

 productiveness. 



THE THEORY OF THE SULPHUS, EEMEDY. 



The oidium, at the commencement of germination, is not only extremely minute, 

 but very sensitive to caustic influences, and easily destroyed, while the leaf of the vine 

 is not easily offended. The sulphur, when minutely divided, so as to form an' impal- 

 pable powder, as is the case when it is finely sublimed, and when it is thoroughly dry, 

 is easily brought into slow combustion by the action of the sun, and thus produces a 

 very small quantity of sulphuric acid in the form of vapor. It is the product of this 

 combustion that gives the peculiar odor of the fumes of sulphur, and to this is owing 

 its action upon the oidium or mildew. Until this combustion takes place, and the sul- 

 phuric acid is formed, the sulphur remains as inactive as if it were only quartz sand. 



While the sulphur remains moist it has no action, and but very little, compara- 

 tively, when in coarse division ; nor does it act efficiently in cool, moist weather. The 

 sulphur, if applied in a state of dryness, on a dry day, with an active sulphurator, finds 

 lodgment for its fine microscopic particles on every part of the vine ; but it will remain 

 longest in the velvety reticulations of the under side of the leaves, where it is most 



