Appendix.- — Account of the Siamese Twin Brothers. 215 



pointed instrument is applied precisely in the middle of the cord, it 

 is felt by both ; and also for about an inch on each side ; beyond 

 which the impression is limited to the individual of the side touched. 



As to the influence of medicines, taken by one, on the body of 

 the other, it would, I suppose, be inconsiderable ; since the vascular 

 and nervous communications must be very limited. The same re- 

 mark may be applied to most diseases. I do not suppose that a 

 febrile affection, slight in degree, would extend from the one to the 

 other. How it would be with a continued fever, appears to me un- 

 certain. But such diseases as are communicable through the absor- 

 bent vessels, or capillary blood vessels, would readily pass from one 

 system to the other ; as for example, the morbid poisons, syphilis, 

 cowpox, smallpox, &c. 



Those who have resided with them say, that the alvine and urina- 

 ry evacuations take place at about the same intervals in both, though 

 not at the same time. In the function of the circulation, there is a 

 more remarkable uniformity in the two bodies. The pulsations of 

 the hearts of both coincide exactly, under ordinary circumstances. I 

 counted seventy three pulsations in a minute, while they were sit- 

 ting ; counting first in one boy, then in the other. I then placed my 

 fingers on an arm of each boy, and found the pulsations take place 

 exactly together. One of them stooping suddenly to look at my 

 watch, his pulse became much quicker than that of the other ; but 

 after he had returned to his former posture, in about a quarter of a 

 minute, his pulse was precisely like that of the other boy. This hap- 

 pened repeatedly. Their respirations are, of consequence, simulta- 

 neous. 



This harmony of action in primary functions, shows a reciprocal 

 influence, which may lead to curious observations and important de- 

 ductions. Observations to be useful, would require much time and 

 great accuracy. 



Among the curious questions which have arisen in regard to these 

 individuals, one has been made as to the moral identity of the two 

 persons. There is no reason to doubt that the intellectual operations 

 of the two are as perfectly distinct, as those of any two individuals, 

 who might be accidentally confined together. Whether similarity of 

 education and identity of position, as to external objects, have in- 

 spired them with any extraordinary sameness of mental action, I am 

 unable to say ; any farther, at least, than that they seem to agree, in 

 their habits and tastes. 



