MALPIGHI 163 



artery discharged its blood, to be there mingled with 

 air drawn in from the windpipe, and then collected by 

 the branches of the pulmonary vein, had no real exist- 

 ence. The vascular networks of the mesentery and the 

 bladder of the frog showed the same kind of com- 

 munication between artery and vein as the vessels of 

 the lung. 



Fracassati's share in the discovery seems to have been 

 unimportant, and two of his letters, printed by Mal- 

 pighi, present him to us as a rhetorical man, not likely 

 to give much effective help. Malpighi, in his second 

 letter to Borelli, writes in his own name, and relates 

 just what he had seen with his ow^n eyes. Borelli 

 advised instant publication, and a printed account, con- 

 sisting of the two letters, was put forth with the least 

 possible delay. ^ 



Thus was Harvey's doctrine of the circulation com- 

 pleted. Few great discoveries in physiology have been 

 made so rapidly, though Aselli's detection of the lacteals 

 furnishes a fair parallel. Malpighi had a clear question 

 in his mind, and knew upon what object he could best 

 direct his lens ; to a man thus prepared a few minutes 

 may well have sufficed. 



Malpighi was the first to demonstrate the vesicular 

 structure of the lung, the sensory papillae of the skin, 

 the minute structure of the liver, kidney and spleen. 

 He saw what must have been red blood-corpuscles in 

 the omentum of the hedgehog,^ but took them to be fat- 

 globules. 



^ De PulmonihuH ohservationeH anatomicce. Fol. Bonon. 1661. I have not 

 seen this rare tract, but only the reprint in Malpighi's Optra. The Dt 

 Pulmonibus and the Opera Poathuma (pp. 4-6, 104) oonUin Malpighi'i 

 account of his discovery. Foster's Hintory of Physiology givet » tranaUtion 

 of the most important passage in the letters to Borelli. 



^ De (menioy kQ. (1666). 



