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generally worked Ler own cure in certain cases, we were glad to 

 shorten her work by the intervention of medical aid, and the 

 physicians considered the symptoms as well worth their study. It 

 was so with the vegetable kingdom. Among the thousands of 

 plants that lived out their allotted time and ripened, and left 

 healthy seed behind them, few escaped minor complaints, and the 

 study of their symptoms, their causes, and the methods of cure 

 which Nature adopted, could not fail to be of interest to Naturalists. 

 The more obvious cases of self-cure were those which belonged to 

 what might be called the surgical department — cutting and 

 wounding — in the cure of which there was both a likeness and a 

 difference as regards the animal economy. 



When Master Tommy cuts his finger, the blood flows. Here 

 they had the vei*y means of death presented, for it was from loss 

 of blood that men died in battle. But, practically, the injury was 

 trivial — the bleeding stopped from the contraction of the tissues, 

 the surface blood coagulated and formed a plaster, and in a few 

 days all trace of the wound was gone. In like manner, when a 

 branch of a shrub was taken off, whether by the gardener's knife, 

 the browsing of animals, or by a gust of wind, the very state of 

 things that Nature had by all possible means guarded against was 

 now set up. The delicate inner portions were exposed to the light, 

 while the sap, which should have flowed in closed channels, was now 

 suffered to pass freely into the air ; and, theoretically, the plant 

 ought to die, as in fact it would when the injury was extensive, for 

 not only must exhaustion follow the loss of sap, but the atmosphere 

 passing into the vessels would cause it to become thick and incapable 

 of flowing. But this very tendency to inspissation saves the plant. 

 The surface sap coagulated so rapidly as at once to exclude the 

 atmosphere and stop the bleeding, the surface-wood cells hai'dened, 

 and the inner layer of what was once sap assumed the form of 

 cambium. Next year a layer of bai-k was formed over the wound, 

 and all that remained was an outward change of form. It must 

 not, however, be forgotten that in all this there was no intei'fei'ence 

 of what was called " vitality." The flow of sap was due to dialysis, 

 the coagulation to evaporation, and there was no appearance of 

 anything like muscular contraction. 



From this point even outwai'd resemblance between animal and 

 vegetable ceased. The animal cure was a restoration — a replace- 



