4 PHILOSOPHICAL TRANSACTIONS. [anNO 1672. 



the abdomen to the anus, (which I imagine to be the cause of the constant 

 motion of the anus in fowls ; the air having ingress and egress there ; and also 

 that to be the reason why the anuses of fowls are, in malignant distempers, ap- 

 plied to draw the infection out of the body :) I thence conjectured the substance 

 of the lungs to be a complication of a multitude of vesicles with the sanguinQous 

 vessels. And in this opinion I thought myself confirmed, by blowing into the 

 aspera arteria of quadrupeds, when I had cut off part of the exterior membrane 

 of one lobe of the lungs, and found the lungs to rise with unequal protuberances 

 not unlike bladders. 



But this second contrivance, which I am going to describe to you, has much 

 shaken that conjecture. March 2, l6^^, I made a ligature about a dog's neck, 

 and opening both the jugular veins with a pretty large orifice, I let him bleed to 

 death, (using this way to prevent being overcharged, either with any quantity 

 of blood, or with blood coagulated ; both which would have been hazarded, in 

 case I had either strangled the dog, or cut one or both of the jugulars asunder:) 

 immediately I opened the thorax, and tying the vena cava, with all the passages 

 from the left ventricle of the heart, or its auricle, I cut the lungs with the heart 

 and aspera arteria entirely out. To the aspera arteria I fitted a syphon 7 inches 

 long, which I thrust 2 inches in length into the said artery, and fastened it with 

 a strong binding of packthread. This done, I blew up the lungs, and fitting a 

 cork to the end of the syphon, hung them in a chimney to dry. In a quarter of 

 an hour they subsided about a sixth part ; whereupon I ordered a person to 

 watch them, and to blow them up as often as they subsided. Which course 

 continued, they would not the next morning subside a fourth part in three 

 hours. And (excepting three quarters of an inch distance from the circumfe- 

 rence of the lobes, where the thinness of the substance of the lungs gave the 

 external heat the advantage of a sudden passage, and quick dispatch of drying 

 those parts least furnished with moisture,) I did not perceive, making a propor- 

 tionable allowance for the drying of the whole substance of the lungs, any con- 

 siderable subsiding in two days more. But upon the blowing in at the syphon 

 (whose ligature I was now forced to renew,) I could easily feel the air pass 

 through the external membranes, both on the convex and concave sides, towards 

 the extremity of the circumference of the lobes; but most abundantly on the 

 concave side. 



March 5th, I carefully cut off one of the lobes, and the inward structure 

 seemed like a cane or dried flag when transversely cut; and, upon blowing in at 

 the syphon, I fancied the air to come equally out at all the pores I had exposed 

 to view. Whereupon I fixed spittle in several places, and upon fresh blowing 

 found multitudes of bubbles, made in the denudated parts of the lobe. I im- 



