182 
MR. BOLTON ON THE UNITED SIAMESE TWINS. 
with great, difficulty be caught by a single person. They have each the power 
to bend their bodies in all directions, and turn their heels over their shoulders. 
They also often playfully tumble head over heels while on their bed, without 
occasioning the slightest pain or inconvenience in the band. The same degree 
of personal dexterity is evinced by each youth when playing at battledore 
and shuttlecock ; and in all the bodily actions common to both, such as 
running and jumping, a remarkable consent or agreement is displayed with- 
out any apparent conference. These concurrences appear to be the necessary 
result of long continued and extraordinary intimacy. 
In their respective physical constitutions, however, several differences occur. 
The boy on the left, Chang, possesses the more vigorous bodily health of the 
two ; but their intellectual abilities appear equal, for they are alike proficients 
in the games of chess and draughts, although they object to compete with each 
other. In the game of whist, however, they rather prefer not to be partners. 
The tongue of Eng is at all times whiter than that of Chang, and his 
digestion is more easily deranged by unsuitable diet. I have never heard that 
Chang has passed a single day without alimentary discharges, but the con- 
trary lias often occurred to Eng. In general they both obey the calls of nature 
at the same time, and this happens even when these result from the operation 
of medicines. 
It having occurred to me, that the odour given by asparagus to the urine 
would be a test of the extent of the circulation of the blood through both the 
twins, on the 22nd of March I gave that vegetable to Chang with his dinner, 
not allowing any to be given to his brother. On examining their urine four 
hours after this meal, that of Chang had distinctly the peculiar asparagus 
smell, but the urine of his brother was not influenced by it. The next day this 
experiment was reversed, and therefore with reversed results. These trials 
sufficiently prove a fact which was otherwise apparent, — that the sanguineous 
communication between the united twins is very limited. 
On the 9th of December they w r ere both attacked with bronchial catarrhs, 
became pale and languid, coughed severely, and complained of pain in 
their throats ; each of them had also slight pains during strong inspirations. 
Their skins were dry and cold, respirations hurried, pulses ninety beats in a 
minute, rather hard and small ; the tongue of Eng was glazed and pallid as 
