COAGULATION OF THE BLOOD. 
311 
only in reference to that with which we are endowed, for 
we are not ignorant from whom all power emanates. It is 
the strength imparted we desire to employ, knowing what 
the result must be if this be rightly done. The duty is 
ours—the consequences we must he content to leave. 
‘ c Let us, then, be up and doing, 
With a heart for any fate : 
Still achieving, still pursuing, 
Learn to labour and to wait.” 
Extracts from British and Foreign Journals. 
THE CROONIAN LECTURE ON THE COAGULATION OE THE 
BLOOD, DELIVERED BEEORE THE ROYAL SOCIETY, 
JUNE 11, 1863. 
By Joseph Lister, Esq., F.R.S., F.R.C.S. 
[Continuedfrom vol. xxxvi,j!?. 758.) 
It may, perhaps, be argued that the drop of blood employed 
being a small drop, and this small drop having been drawn 
up by suction into the tube, it might have parted with its 
ammonia before it got into the tube; but then (and now 
comes the bearing of the experiment on the effect of tem¬ 
perature) I found, if I placed a similar tube filled in the 
same w 7 ay in a vessel of snow, so as not to freeze it, but to 
keep it ice-cold, the blood in it remained fluid as long as I 
chose to keep it there. Now, if all the ammonia had left the 
blood before it was introduced into the tube, cold ought, 
according to the ammonia theory, to have had no effect in 
retarding its coagulation ; for, according to that theory, cold 
operates by retaining the ammonia. On the other hand, 
if we take the other alternative, and suppose that any 
ammonia which the blood might have contained was still in 
these tubes, the former experiment proves clearly that the 
retention of ammonia has no effect in producing fluidity— 
no effect in preventing coagulation; and if the retention of 
ammonia has no effect in preventing coagulation, then cold 
certainly cannot prevent coagulation by retaining the am¬ 
monia, because, even if retained, it would not influence the 
result. In whatever way we look at them, therefore, these 
