VOL. LXIV.] PHILOSOPHICAL TRANSACTIONS. 573 



passage both uteri would seem to have an equal chance for impregnation ; for, 

 notwithstanding that which contained the foetus was placed almost directly in 

 a line with the axis of the right vagina : yet this probably was not its original 

 position ; but by degrees its bulk increased so much as necessarily to occupy the 

 middle space, and push the unimpregnated one aside. But however surprizing 

 it may seem at first view, yet there was reason to imagine, that the right womb, 

 though at a greater distance, would be much more apt to conceive than the 

 other, if the left vagina only had been made use of. For when this was dis- 

 tended, it appeared that the posterior part of the septum, by its protuberance, 

 closed up and covered the left os tincae ; and as such would probably be the case 

 in copulation, the semen not finding a ready admission into it, would pass over 

 to the right orifice, where its entrance could not be so much obstructed. So 

 that, if he may hazard a conjecture, he thought it more likely, since the right 

 uterus alone conceived, that the left vagina had generally been employed. 



It was a prevailing opinion among the ancients, that male children were con- 

 ceived in the right side of the womb, and females in the left. Having so few 

 opportunities of dissecting human subjects, they depended too much on the 

 analogy of the structure of brutes, which has been the principal source of the 

 many erroneous descriptions met with in their works. It is well known 

 that the uterus of many quadrupeds is divided into 2 cornua, in which the 

 foetuses are lodged; and it was not very absurd to conclude, that nature might 

 have formed them for the distinct repositories of the 2 sexes. Accordingly this 

 was supposed to take place in the human uterus, which has been described and 

 delineated as if distinguished into 2 chambers. Hence arose the opinion, which 

 is received in some places to this day, that a very sure prognostic, with regard to 

 the sex of the child, may be drawn from the side of the belly on which the 

 tumour is more sensibly felt. Dissections, being now more frequent, have proved, 

 that the human womb generally has only one undivided cavity ; so that the foetus, 

 let it come from which tube it may, will, when arrived to a certain size, occupy 

 it entirely. This observation however is not sufficient to refute the supposition 

 that each sex might have its peculiar ovarium ; and some authors pretend, that 

 they are able to determine how many males or females any animal has brought 

 forth, by examining the number of cicatrices on its ovaria. For, when females 

 only had been produced, the right ovarium was found still full of vesicles, but 

 the left quite exhausted. That this is not always the case in brutes, appears 

 from the observation of Dr. Harvey, wlio frequently found male foetuses in the 

 left cornu, and females in the right. In the human subject, opportunities of 

 ascertaining this matter must occur very seldom. We have an instance, 

 recorded by Cyprian, where both a boy and a girl were conceived, though the 

 right tube was wanting. But the present case affords another example, which is 



