January 24, 1908] 



SCIENCE 



131 



functions are maintained and, as a rule, in 

 a perfect manner. Hence it now becomes 

 possible to place sensitive and important 

 viscera under new experimental conditions 

 which may aim to resemble or to reproduce 

 those believed to give rise to common patho- 

 logical states in man, and to observe the 

 effects over a long period of time. This 

 method, in the hands of Carrel, its chief 

 exponent, has already produced many new 

 and highly important results relating to 

 the blood-vessels, the kidneys, thyroid 

 gland and other organs. It is a matter of 

 no small theoretical and practical signifi- 

 cance that arteries can be transplanted suc- 

 cessfully from dog to cat, and vice versa, 

 and from man to dog, and that keeping 

 extirpated arteries under sterile conditions 

 at refrigerator temperature for twenty or 

 thirty days, or even longer, does not inter- 

 fere with the results of transplantation; 

 and the histological changes suffered by 

 the transplanted vessels, whether in the 

 same or different species, or made imme- 

 diately after removal from the body or 

 after several weeks in cold storage, are 

 small in conformity with their perfect 

 function as blood vessels. 



The knowledge of the processes of in- 

 flammation has already been, and medical 

 and surgical practise may hope to be, 

 assisted by studies of the leucocytes from a 

 physiologico-chemical point of view. The 

 indispensable phagocytic function of the 

 leucocytes— whether directed against mi- 

 cro-parasites or somatic cells worn out 

 by physiological use or destroyed by patho- 

 logical effects— is now so generally ad- 

 mitted that it seems trite merely to men- 

 tion the property. But this living function 

 of the leucocytes is supplemented by their 

 demonstrated power to yield upon dissolu- 

 tion active proteolytic enzymes of con- 

 siderable potency capable of attacking na- 

 tive and alien proteid. This enzymotic 

 action can be and often is held in check 



by certain antienzymes contained normally 

 in the plasma of the blood. Opie, to whom 

 we owe the discovery of the antienzymotic 

 power of the blood-servim, has shown, also, 

 how greatly the issue of an inflammation 

 is affected by the balance between the 

 leucocytes and the serum, and how a puru- 

 lent inflammation with solution of tissue is 

 the product of collections of leucocytes 

 whose enzymotic power is unrestrained by 

 sertim, and that the more superficial and 

 less destructive sero-purulent exudations 

 have the potential enzymotic activity of 

 the leucocytes balanced and checked by the 

 serum. It would appear not to be a long 

 or particularly difficult step from the estab- 

 lishment of these conditions by experi- 

 ments on animals to their application in 

 human beings in whom the issue of inflam- 

 mations may be promoted in the direction 

 offering the best hope for the patient. 



Until recently, all progress regarding 

 tumors, excepting in their histological 

 structure and place of origin, has been in 

 respect to their surgical treatment. Im- 

 provement in operative methods by which 

 local infection of the site of operation and 

 general dissemination of tumor cells have 

 been avoided, and the more complete re- 

 moval of all tumor-infected tissue accom- 

 plished, have increased greatly the number 

 of cures of malignant tumors. We are 

 still ignorant of the cause of tumors, and 

 there is no likelihood that the ignorance 

 will soon be dispelled. But the study of 

 transplantable tumors in mice and rats, 

 chiefly, has already yielded many im- 

 portant facts concerning the biological con- 

 ditions underlying tumor growth. These 

 small animals, the domesticated races espe- 

 cially, are not infrequently the sub.ject of 

 spontaneous tumors which compass their 

 death. The tiunors are, therefore, malig- 

 nant ; in mice they are carcinomata, chiefly, 

 springing from the mammary glands; in 

 rats, sarcomata, chiefly, taking origin from 



