180 
MR. BOLTON ON THE UNITED SIAMESE TWINS. 
entered, and which I have no doubt contained two sets of vessels*. Small 
blood-vessels and nerves must of course traverse the substance of the band, 
but no pulsation can be detected in it. 
Captain Coffin and Mr. Hunter were informed by the mother of the twins, 
that soon after their birth, and during the period of infancy, this band was 
much larger in proportion to the size of their bodies than it is at the present 
time : it had then no hard cartilaginous feel at its upper margin ; it was also 
larger in circumference, and the bodies of the twins were nearer in contact ; 
but from continued stretching it has become elongated, and its circumference 
has diminished. In their own country they were employed to row a boat, 
for which purpose both stood at the stern, each using a one-handed oar, an 
exercise which must have assisted greatly in stretching the band. It is now 
remarkably strong, and possesses little sensibility ; for they have been formerly 
pulled by a rope fastened to it, without complaining of pain, or expressing any 
uneasiness. In the month of February last one of them fell out of bed while 
asleep, and hung by the band for some time, and when both awoke, they alike 
stated, that they experienced no pain in the band from this accident. Mr. Hale, 
their constant attendant, has lifted one of them from the ground, allowing the 
other to hang by the band with his feet raised from the floor ; yet the whole 
weight of one of the boys thus suspended did not occasion pain to either, or 
even excite their displeasure. The circumstance of the small degree of sensi- 
bility possessed by the band, tends to corroborate the opinion I entertain of 
the possibility of effecting a separation of the twins by a surgical operation. 
* It has been asserted, that “these twins are the produce of a single ovum, and grew upon one 
placenta, by one umbilical cord but of this there does not appear to be any evidence. By permis- 
sion of the Board of Curators, I have had an opportunity of examining a preparation of united female 
twins, now in the museum of the Royal College of Surgeons in London. The union extends from the 
lower part of the sternum of each twin to the navel ; and there is one umbilical cord common to both. 
On dissection, the following appearances were observed. — The umbilical vein in its course towards the 
twins, is divided into two nearly equal sized branches, the division taking place at about one inch 
and three quarters from the umbilicus ; one branch passing upwards in front to the porta of the 
anterior liver, and the other behind to its proper liver. The number of arteries are four, two from 
each foetus, and are included in the same theca with the umbilical vein as far as the body, retaining 
the appearance of an ordinary funis. 
