4,10 Messrs . Allen and Pepys on Respiration. 
been furnished with the lungs of a stout man, about five feet 
ten inches high, taken from the body not long after death, 
and in a sound state, we proceeded to ascertain the quantity 
of air contained in this organ after the most complete expira- 
tion, as in death. 
Henry Cline had judiciously taken the precaution to divide 
the trachea just below the crichoid cartilage, before he opened 
the thorax ; he then inserted a tube with a brass stop-cock, 
which he tied firmly to the trachea, and attached an empty 
bladder to the other end. The cock was then turned, so as to 
communicate with the bladder, and on opening the thorax 31- 
cubic inches of air were expelled into it. The weight of the 
lungs was four pounds one ounce. A very large glass jar 
being placed in a shallow tin vessel, was filled to the brim 
with water, the lungs were then completely immersed, and 
the water which flowed over, and was the measure of their 
volume, weighed six pounds two ounces ; we next cut a por- 
tion of the lungs into small pieces, under a large inverted glass 
of water, and attempted to squeeze the air from the cells, but 
although several cubic inches were thus procured, we were 
soon convinced that it was utterly impossible to arrive at our 
object by these means, as no force that we could use seemed 
capable of expelling the air from the cellular membrane, into 
which it escaped from the vesicles. We therefore took por- 
tions of the lungs, which weighed 2774, grains ; the mass 
being put into a piece of new hair cloth, was subjected to the 
action of a powerful screw press, and the fluid was received 
in a vessel ; after twice undergoing this operation, the mass 
weighed only 66 o grains. Its specific gravity was very nearly 
that of water, viz. ,930 water being 1 ,000 : the fluid procured 
