VOL. LXXXVII.] PHILOSOPHICAL TRANSACTIONS. 123 



facts militate strongly against the possibility of the conveyance of the semen to this 

 part vi jaculationis, and demonstrably prove, as far as 3 facts can go, that if the 

 moving power inheres in the female, it is not instantaneously exerted. 



But are the powers of the fecundating fluid conveyed at any time by the tubes ? 

 This simple question betrayed me into the prosecution of experiments to a greater 

 extent than I at first expected ; for the result of several of them was unsatisfactory : 

 but being once engaged in the question, I felt myself compelled to prosecute it, by 

 examining these parts at different periods from the coitus to the manifestation of its 

 effects. But I found from a regular series of observations made on different rabbits, 

 at every hour between the 1 st and the gth, that the fimbriae remained nearly in 

 their usual situation ; and the only difference I perceived in the last hours, was a 

 greater turgescency of vessels, as is preparatory to some important action. I de- 

 sisted from this inquiry at the 9th hour, because the ovaries now bore very evident 

 marks of impregnation ; and there appeared to have been no action in the tubes by 

 which the semen could have been conveyed to them. 



The impression which these experiments at first made on my mind was, I must 

 confess, not altogether incongenial to my wish, inasmuch as they seemed to 

 furnish a satisfactory answer to the question : but reflections when more at leisure 

 abated my confidence, and in the end convinced me that my proofs did not exceed 

 probability, so that there was still room for the suggestions of scepticism : and in- 

 deed it might be said with great propriety, that the tubes might have inclined to- 

 wards the ovaries in the intervals of the hours above-mentioned, and have returned 

 to their former situation, and thus have eluded my research. I think it but candid 

 to acknowledge, that these last experiments do not prepare me to meet that 

 objection. 



These reflections suggested to me the expediency of constructing a plan of in- 

 quiry more apposite to the subject ; and attended with experiments bearing more 

 directly on the point at issue. Under this impression I determined to obliterate one 

 of the tubes at different periods post coitum, and after the lapse of a sufficient 

 length of time, to notice the effect. My particular view in this was to allow suffici- 

 ent time for the arrival of the semen at the ovaries, supposing it to take place ; so 

 that if they were stimulated by an affusion of that fluid, either in a palpable or in- 

 sensible form, here would be time allowed sufficient to produce its effect ; and if in 

 this mode foetuses could be formed, while by obliterating the tube ante coitum no- 

 thing more than corpora lutea were seen, it furnished an argument of no incon- 

 siderable force in favour of impregnation by immediate contact ; but if, on the con- 

 trary, corpora lutea only were found, then such experiments would give additional 

 force to the arguments stated in a former part of this section. 



Exper. One of the tubes of a rabbit was divided 4- an hour post coitum, and the 

 wound closed as before. She was kept a fortnight, that I might know the result; 

 but there were no marks of impregnation on either side. Though a failure of im- 



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