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its silent but certain and destructive operations. 

 When the buds are dead, they, like all dead vegetable 

 matter, become powerful absorbents of water, whether 

 of the finely-divided vapours of the atmosphere, or the 

 more condensed form of rain-water — hence, after rain, 

 they become gorged with water. So long as these 

 dead buds rest on the trees, there is httle or no cica- 

 trization between the dead buds and the branches 

 which they rest on ; or, at all events, not before they 

 have been saturated with moisture, which first satura- 

 tion, after death has taken place, enters into the most 

 incipient fermentation with the sap of the plant, at 

 the connection between the dead bud and the living 

 branch. By the alternations of wintry weather, from 

 wet to dry, and wet to frost, and frost to hot sunshine, 

 as spring approaches, the frost, freezing the water in 

 the dead buds, enlarges their capacity for holding 

 their destructive element, which assists in carrying on 

 the fermentation between the alburnum and the bark. 

 In this infant stage of the disease, it is not discernible 

 by ordinary observation, as the bark does not change 

 its colour for some time after the disease has entered 

 the system of the plant ; and, if dry weather follow 

 the recent establishment of it, its ravages are arrested 

 for a time, but which, nevertheless, progress as the sap 

 attenuates, when the disease again, but more plainly, 

 manifests itself. 



xlnother cause for gumming is a local contraction 



