152 EMBRYOLOGY IN THE SEVENTEENTH [pt. ii 



a perfectly sound deduction from Harvey's experiments, and did not 

 then appear anything like so unsatisfactory as it does now, for Gilbert 

 of Colchester was not long dead, the "lodestone" was beginning 

 to be investigated by the virtuosi, and even such extravagances as 

 Sir Gilbert Talbot's Powder "for the sympatheticall cure of wounds" 

 were only with difficulty distinguishable from the real effects of 

 magnetic force. Harvey's idea of fertilisation by contagion has recently 

 been in a sense revived by the work of Shearer (see Section 4*2). 



But to Harvey himself the subject of the action of the seed was 

 hid in deep night, and he confessed that, when he came to it, he 

 was "at a stand". Some very interesting light is thrown upon his 

 mind in this connection by a copy of the De Generatione Animalium 

 annotated by himself, and now in the possession of Dr Pybus, by 

 whose courtesy and by that of Dr Singer, who has transcribed the 

 notes, I have been enabled to study it. It was given by Harvey to 

 his brother Eliab, whose name it still bears. The notes, which are 

 on the fly-leaves, are written in much the same way as those famous 

 ones which Harvey used for his lectures at the College of Physicians in 

 London, and which have been reproduced in facsimile. There is the 

 same mixture of Latin and English, and the same signs, such as WI, to 

 denote thoughts claimed as original. A page is reproduced in Fig. 7. 



For the most part, the notes are uninteresting and nothing but a 

 confusion of Aristotelian terms. But one page is concerned with the 

 mode of action of the seed, and here we can, as it were, see Harvey's 

 mind wrestling with this most difficult of problems. He sees that 

 odour and the sense of smell may give a clue. That his thoughts on 

 this point were doomed to frustration as soon as eggs and spermatozoa 

 were discovered does not detract from the interest of the struggle. 



Quod facit semen fecundum 



What makes the seed fertile is on the analogy of an injection. In fact, 

 the injection causes disease in many cases, and that from a distance, both 

 by another. . .and by the same. . . A Venereal (?) disease corrupts coitus 

 with a woman in whose uterus is the poison. 



They do not [or do not yet ?] come forth in actuality but lie dormant 

 as in fuel [? fomite]. Again, rabies in dogs lies dormant for many days 

 on my own observation W4. Again, smallpox for days. Again, the genera- 

 tive seed, just as it (passes) from the male, lies dormant in the woman as 

 infuel(?). 



Or else like a . . . , like light in stone . . . , the pupil in the eye, in sense 

 motion, ... in the body. 



