434 Dr. Williams on the Practicability of [June, 



parent, as remarked by Prof. Richerand.* We could perceive 

 very distinctly the ramifications of the coronary vessels ; the 

 diaphragm was in its natural position ; no adhesions ; the lungs 

 on first exposing them appeared perfectly smooth and glossy ; 

 in a little time they were slightly corrugated by the effect of the 

 cold in condensing the enclosed air : the examination was con- 

 ducted in the open air. Not the slightest difference could be 

 {>erceived either in the expansion or general appearance of the 

 ungs of the two dogs. Their lungs did not extend by two 

 inches to the inferior part of their respective cavities, and their 

 bulk was insufficient to fill the remaining part of the bags of the 

 pleura. Pray what proof is there that the lungs fill the bags of 

 the pleura ? I must confess that I am quite sceptical upon that 

 point, and, on the contrary, believe that in a healthy state they 

 never fill them. To prove that the measure we had recourse to 

 was effectual in preventing the air escaping out of the lungs, 

 when the chest was opened at the conclusion, we divided the 

 windpipe of each below the knots, when they instantaneously 

 collapsed. 



Exper. 6. — The description supposes the animal to be stand- 

 ing upright on his hind legs. The right cavity of the chest was 

 transfixed with a sharp-pointed penknife, by thrusting it trans- 

 versely with a slight degree of obliquity downwards, through the 

 intercostal space, immediately above the upper edge of the 

 eleventh rib, mid-space, between its head and anterior extre- 

 mity. The animal was afterwards put to death. Dissection: 

 the instrument had pierced the diaphragm, and had slightly 

 wounded the liver ; the lung uninjured ; the knife had passed as 

 near as possible through the centre of the cavity at that part, 

 and but little short of two inches above its inferior termination. 

 Had the lung extended so low down, it must have been wounded, 

 the knife being sharp-pointed, and pushed in with force. 



Exper. 7. — To remove every doubt, with respect to the slate 

 of the lung, when deprived entirely of the influence of the aux- 

 iliary respiratory organs, the following experiment was made in 

 the open air. The cartilages of all the true ribs were divided, 

 with the exception of the superior one, close to their juncture, 

 with the osseous structure, and the left cavity of the chest laid 

 open its whole length ; the diaphragm was punctured ; the ribs, 

 and their cartilaginous ends, attached to the sternum were sepa- 

 rated and retained asunder, so as to expose and to deprive the 

 lung of every assistance from the auxiliary respiratory organs. 

 The lung rested upon the ribs and side of the vertebrae ; on ex- 

 posure, it shrunk considerably, but did not collapse. Its motion, 

 for it was not. at rest, might be compared to that of a leech when 

 it draws up, and again recedes its body, without making any 

 progression ; indeed, with both ends fixed, the motion was not 



• Edinburgh Medical and Surgical Journal, vol. xiv, p. GiJ. 



