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1 have said that the decay affected the soundest and finest fruit, as 

 well as that of an opposite description ; and from this I concluded that 

 the cause, whatever it might be, was of a local and not of a constitu- 

 tional character. The supposition, therefore, that the decay, in those 

 instances in which it occurs in sound fruit, arose from enfeebled vita- 

 lity of the whole fruit affected, would not afford a satisfactory expla- 

 nation. Since if that were the case, every part of a fruit, an apple or 

 pear for example, about to pass to decay, ought to be equally and si- 

 multaneously attacked. Neither would the opinion that the decay 

 was the result of diminished vital energy in the bruised or injured 

 portion of the fruit, be any more satisfactory, unless it were argued 

 that fruits were subject to an inflammatory process, for how otherwise 

 could the extension of the decay to the sound portion of the fruit be 

 accounted for ? But a third attempt at an explanation may be made, 

 on the ground that atmospheric air enters more readily into the bruis- 

 ed portion of the fruit, and that its oxygen, combining with the ele- 

 ments of the contents of the injured cells, forms deleterious compounds 

 which effect the decomposition of the sound portion. But the falsity 

 of this view is easily proved by the fact that it is rather unfavourable 

 to the form of decomposition here spoken of, as may be demonstrated 

 by a simple experiment. If apples divided with a knife be exposed 

 to the air, together with such as are bruised, the skin not being rup- 

 tured, the decay of the bruised part will result more quickly than that 

 of the simply incised fruit. 



Seeing therefore the deficiencies of the only explanations which it 

 appears to me could be suggested of the particular form of decay 

 which so generally affects fruits of the apple and peach tribes, I am 

 compelled therefore to have recourse, for a consistent explanation, to 

 the Fungus which I have this evening introduced to the notice of the 

 Members of the Microscopical Society. 



But it must not be supposed that I am going to deny the possibi- 

 lity of an apple passing to decay in the same manner as other organ- 

 ized substances, whether animal or vegetable, namely, by the laws of 

 chemical action operating upon their substances, the animating prin- 

 ciple having fled from its temporary tenement ; but the decay, the 

 result of a general loss of vitality, is very different from the form of 

 decay which has this evening been discussed, which may have, and 

 frequently has, its seat in the fruit while it is still upon the tree, firm, 

 juicy and life-like. 



Liebig, in his philosophic work on Organic Chemistry, divides the 

 processes of organic decomposition into those of fermentation, putre- 



