VOL. VII.] PHILOSOPHICAL TRANSACTIONS. 5 



mediately made a deep transverse incision into that lobe, and blowing in at the 

 syphon, found the air to come so freely out at the larger ramifications of the 

 bronchia, that I could not give the lobe a considerable rise with a strong blast: 

 yet upon stopping with my fingers the larger passages of the bronchia, which I 

 had cut, I found that lobe upon a fresh blast, rise considerably with unequal 

 protuberances (where the incision was made) giving no small suspicion of some 

 latent vesicles. Hereupon I tied that lobe above the incision, and taking off 

 part of the external membrane of another lobe, (having first tied up all the rest 

 of the lobes) I poured water into the syphon, and applied a strong blast, in 

 hopes to have the water come forth in streams at all the pores; but that did not 

 satisfactorily succeed, it coming out in a confused irroration of the external 

 surface, without any ebullition, unless at the larger ramification of the bronchia. 

 Then I tied up this second lobe, and untied a third, pouring in an ounce of the 

 oil of turpentine; at the syphon I gave a small blast, and corked it up. Two 

 hours after I took off" the small membrane of that lobe, and upon a gentle blast 

 at the syphon found an ebullition of infinitely small bubbles. 



March 10, (having continued it to the chimney) I cut all the lobes in pieces 

 by different and various irregular incisions; whence I could easily observe the 

 several ramifications of the aerial and sanguineous vessels, with their continua- 

 tion to the circumference of the lobes, and a proportionable diminution as they 

 were at a further distance from their original. 



Shall I hence conclude the structure of the lungs to be a complication of a 

 multitude of the ramifications of the bronchia and sanguineous vessels ? and 

 that the seeming vesicles were occasioned only by the violence of the blast, and 

 the dryness of the extreme and smallest passages of the aerial vessels ; where- 

 upon those, nearest to the bronchia (being moister) were, more than their or- 

 dinary proportion, extended, upon hindrance of a free and usual passage to the 

 air in the lesser vessels or their extremities ? * 



Soine Astronomical Observations in part already made, partly to he made. 

 By Mr. John Flamsteed. N° 86, p. 5034. 



These prognostications and observations are now no longer of any use. 



* The forcible inflation here resorted to is a great objection to deducing any conclusions from these 

 experiments, which mdeed appear to be of little value. The bronchial tubes, which are ramifica- 

 tions of tlie trachea, ultimately lose their cartilaginous structure, and terminate in membranous vesi- 

 cles or cells, which in the act of inspiration become distended with air. Upon the surfaces of tliese 

 air-cells are spread the minute ramuli of the pulmonary blood-vessels, so as to have their contained 

 fluid (the blood) subjected to the chemical action of the air; not indeed by immediate contact, but 

 with no other intervening medium than the exquisitely thin coats of the distended vesicles or ceils. 



