DIFFERENTSYSTE M S. 85 



enter the mixture, give life to it, and cover its 

 furface with ;i pellicle, which alFumes a round 

 figure, becaufe the fpirits adling in the centre, 

 expand the matter equally on all fides. I have 

 feen, fays this great phyfician, a foetus of fix 

 days old : It was a ball of hquor inclofed in a 

 pellicle. The liquor was reddifli ; and the 

 pellicle was interfperled with red and colourlefs 

 veflds. In the middle of it there was a fmall e- 

 minence, which i apprehended to be the umbi- 

 lical veiTcls, by which the foetus receives nou- 

 rilhment and the fpu'it of refpiration from the 

 mother. A fecond covering or peilicle gradu- 

 ily forms above the firft. Abundance of nou- 

 rifliment is furniflied by the menftrual blood, 

 which coagulates by degrees, and is converted 

 into flefli. This flelh gradually articulates as it 

 -rows ; and the Ipirit beftovvs upon it this form. 

 Every part aliumes its proper place ; the folid 

 particles unite ; the moid particles ailbciate by 

 themfelves ; every thing fearches fcr what 

 is analogous to it ; and, in fine, tlie foetus, 

 by thele caufes and means, is completely form- 

 ed. 



This fyftcm is more rational, and lefs obfcure 

 than that of Ariflotle; becaufe Hippocrates en- 

 deavours to explain every particular appearance, 

 and borrows one general principle only from 

 the philofopliy of his times, namely, that.lieat 

 and cold produce fpirirs, and that thefc Ipirits 

 •have the power of arranging and of bellowing 



F 3 figure 



