THE GERM-THEORY OF DISEASE. 



515 



tions at whose bidding they appear. The ele- 

 ments of the proof are these : 



(a.) First, there is the evidence which has been 

 adduced by various observers as a result of the 

 study by the microscope of the mode in which 

 organisms appear within tissue-elements. I do 

 not lay much stress upon this here, because evi- 

 dence of such a nature is more open to various 

 objections than that which is to follow. 1 



(b.) Although the blood and internal tissues 

 of healthy animals and of man are free from in- 

 dependent organisms and their germs, yet such 

 organisms will habitually show themselves after 

 death, in the course of a few days, throughout 

 all the organs of one of the lower animals or of 

 man — even when life has been abruptly termi- 

 nated during a state of health. It cannot be 

 said, in explanation of this, that the organisms 

 naturally present in the intestinal canal have 

 been enabled to spread through the body so as 

 to reach its inmost recesses after death — since 

 many of the organisms found are motionless, and 

 others have mere to-and-fro movements of a non- 

 progressive character. The blood, again, has 

 ceased to circulate, so that this fluid, germless 

 during life, cannot after death be considered to 

 act even as a carrier. If the organisms them- 

 selves cannot make their way through the tissues, 

 and if no carrier exist, they must naturally have 

 been born in or near the sites in which they are 

 found. 



Phenomena of this kind are to be witnessed 

 even in insects, such as silk-worms and flies ; and 

 the organisms that habitually develop in them 

 after death are, as in the case of higher animals, 

 just such organisms as appear in some of their 

 best - known contagious diseases. 2 Certain of 

 these diseases, like " muscardine," seem to be 

 generable de novo at the will of the operator by 

 merely placing the animal for a few days under 

 particular sets of unhealthy conditions. 



(c.) Some of the ferment-organisms may also 

 be made to appear at will in certain parts of still 

 living and previously healthy animals by deter- 

 mining in any such part either (1) a greatly low- 

 ered vital activity, or (2) an active perversion of 

 the nutritive life of the part of considerable in- 

 tensity : 



1. This subject has been studied experimen- 

 tally by Messrs. Lewis and Cunningham, 3 two 



1 On this subject see "Beginnings of Life," vol. ii., 

 p. 342. 



2 Ibid., pp. 327, note 1, and 330, and " Transactions 

 of the Pathological Society," 1875, p. 343. 



3 "The Fungus-Disease of India," Calcutta, 1875, 

 p. 89. 



thoroughly competent and trustworthy observers, 

 whose researches during recent years have won 

 for them a deservedly high reputation. They 

 say: "The object of the experiments was to as- 

 certain whether, by interfering with the vascular 

 supply of certain tissues and organs of the body 

 of an animal without injuring the isolated tissue, 

 we should be able within the course of some hours 

 to detect organisms in those parts in the same 

 manner as we had been able to do when an ani- 

 mal had been killed under chloroform and set 

 aside in a warm place. We found that such was 

 the result, and that a kidney, for example, when 

 [its artery was] carefully ligatured without inter- 

 fering with its position in the abdomen, would be 

 found after some hours to contain precisely sim- 

 ilar organisms ; whereas the other kidney, whose 

 circulation had not been interfered with, con- 

 tained no trace of any vegetation whatever." l 



2. Facts of this second order have been thor- 

 oughly established by the important researches 

 of Prof. Burdon-Sanderson. He says : 2 " If a few 

 drops of previously boiled and cooled dilute solu- 

 tion of ammonia are injected underneath the skin 

 of a Guinea-pig, a diifuse inflammation is pro- 



1 On September 17, 1877, 1 had an opportunity of 

 seeing how far this would hold good for the human 

 subject. On that day I made an examination, twelve 

 hours after death, of the body of a young man who 

 had been suffering from severe beart-disease in Uni- 

 versity College Hospital. His temperature bad only 

 been slightly raised for about forty-eight hours before 

 death ; but there was reason for believing that em- 

 bolic obstructions had recently occurred in one or 

 both kidneys. Abundant "vegetations " were found 

 on the mitral and aortic valves, and two or three em- 

 bolic patches existed in each kidney, some being re- 

 cent and others ef older date. One large yellowish 

 embolic patch was likewise found occupying the upper 

 extremity of an enlarged spleen. Some blood from 

 the right ventricle and some urine from the bladder, 

 carefully removed with capillary tubes, on examina- 

 tion with the microscope and a one-twelfth object- 

 glass, showed no organisms of any kind. Portions 

 of tissue cut from the interior of the liver also showed 

 no organisms. On the other hand, the embolic patch 

 in the spleen as well as those in the kidney, both old 

 and recent, showed, when portions of their disin- 

 tegrated substance were examined, organisms, more 

 or less abundantly distributed, similar to those which 

 Messrs. Cunningham and Lewis have figured. Some 

 were Bacilli, and some were more like what Cohn 

 now distinguishes as Vibriones. They were not so 

 abundant as to be always found without careful exam- 

 ination ; and, on the other hand, in the diseased splen- 

 ic tissue there were a multitude of small acicular crys- 

 tals which an inexperienced observer might mistake 

 for motionless organisms. In the lower healthy por- 

 tion of the spleen no onrnnisms were found. 



2 "Transactions of the Pathological Society," 1872, 

 pp. 306-308. 



