REPARATORY INFLAMMATION IN ARTERIES. 21 



the march of the vascularization of a thrombus in a ligated 

 vessel. To ray surprise, I was unable in any single instance to 

 find under the microscope appearances in my sections of thrombi 

 which could to my mind be fairly considered as confirmatory 

 of the foregoing statements of Billroth and Rindflcisch, either 

 as to the formation, the constitution, the organization, the 

 vascularization, or the obliteration of the blood-clot. 



After having given to Dr. Agnew the results of the examina- 

 tion which I had undertaken for him, I inaugurated for myself a 

 more thorough and sj'stematic experimental study of the whole 

 question of the manner and the means by which a ligated 

 artery is healed. This second investigation was conducted at 

 odd times, and had extended in this way over a year and a 

 half, when, at the commencement of January of IStt, I deter- 

 mined to embody the results I had attained in an essay, which 

 secured for me the award of the Warren Triennial Prize for 

 that year. Since then, as occasion has offered, I have from 

 time to time added to the number of my experiments and 

 observations, and have pushed them into the question of the 

 healing of an artery after acupressure and torsion as well. 

 The conclusions based upon the entire series of observations 

 are more comprehensive than those derived from my first 

 stud}^, and, in a few points, are slightly different. 



Upon the healing of arteries four regular series of prepara- 

 tions have been secured, the experiments principally being per- 

 formed upon the femoral arteries of 3'oung, vigorous dogs. 



In obtaining the fir-i^t series the following order has been 

 observed, viz.: the artery was exposed and tied in continuity 

 with the ordinary silk ligature, the thread being allowed to 

 remain on the vessel until the animal was killed, or until it 

 came away without assistance. The subjects were then killed 

 in rotation at such times as to afford preparations of their 

 arteries, 24, 36, 48, and 94 hours, and 5, 8, 10, 15, and 21 days 

 after ligation. Each number of this series w^as duplicated, 



