HISTIOID TUMOURS. 145 



come to study the details of this sort of '^ closure by swelling," 

 we shall find it necessary to admit that it may very probably 

 retard the progress of infection. The delay, however, is never 

 more than temporary; it never amounts to an arrest of the 

 process. 



§ 120. The third and last period in the propagation of the 

 tumour shows us that even the sacrifice of several lymphatic 

 glands has not j^reserved the organism from constitutional 

 disease. The production of secondary deposits in other regions 

 of the body is known as metastasis. Whether this designation is 

 justified by the actual transfer of material particles from the seat 

 of primary mischief and the diseased glands to more remote 

 parts, is open to all the doubts previously expressed; the most 

 active investio^ation has hitherto failed to demonstrate the 

 tumour-elements in the blood, through which their transit must 

 inevitably take place ; so that here also, prudence bids us confine 

 ourselves for the time being to the hypothesis of some zymotic 

 material existinor in the blood. 



Whoever rejects the theory of a dyscrasia, sees in this radia- 

 tion of the formative stimulus from the seat of primary disease a 

 summary presentment of the relation in which every malignant 

 growth stands towards the organism. He who su2:)ports the 

 doctrine of a primary constitutional disorder occupies a far more 

 difficult position. He may insist however : 1st, that the cachexia 

 cannot as yet be fairly identified with the constitutional Infection, 

 and 2nd, that the formative stimulus must be the same for the 

 ])rimary tumour as for the secondary deposits ; and that the 

 difficulties in the way of explaining the origin of the primary 

 tumour, save on the hypothesis of an antecedent dyscrasia, 

 remain as great as they ever were. For my own part, I do not 

 feel called upon to anticipate in any way the coming solution of 

 this problem. 



§ 121. Having agreed upon the clinical significance of 

 malignity, we may proceed to Inquire, whether there are any 

 anatomical signs by which malignant tumours may be recognised, 

 before their malignity is proved by the occurrence of metas- 

 tasis ; to this inquiry, we return the same answer as Waldei/e)', 

 namely, that tumours tend as a rule to become generalised in 

 direct i^roportlon to the vascularity of the soil in which they 

 grow, and to the number of mobile cells present in their 



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