4J'4 ESSAYS AND OBSERVATIONS 



acquainted with their origin. De Graaf ^ 

 attempted in vain to dilcover this by ma- 

 ceration in water ; nor have anatomiftSj 

 iince his time, been more fuccefsful. 



I have endeavoured feveral times to 

 fore-" quick-iilver from the fpermatic arte- 

 ries into the feminal vefTels; but, though 

 I made it return by the fpermatic veins, 

 I could never caufe it to pafs into thefe 

 convoluted tubes. 



This I attempted the oftener, becaufe 

 of the feeming probability of our being 

 able to determine, better in this than in 

 other glands, whether fecretion is per- 

 formed in continued cylindrical canals, 

 according to Ruyfch, or, by the mterven- 

 tion ot follicles, with Malpighius j fince 

 we can feparate the parts of the tcflicle, 

 without cutting, and even almoft without 

 laceration. 



• De vir. org, p, 42. 



Art. 



