98 REPORT— 1839. 



inasmuch as they were delayed for ages by the existence of the theory, 

 which considers inflammation a sanative process, and as their success- 

 ful applications furnish so many proofs of the falsity of this opinion. 



Dr. Macartney, after exposing the errors in practice to which this 

 error of hypothesis has led, explained some new views on the subject. 

 In his opinion the common ligature, when it does not succeed, in 

 almost every instance fails from creating irritation, and consequently a 

 dilated state of the arteries, or their ulceration ; although much 

 depends on the plan of after treatment in repelling inflammation, still 

 the parts feel the presence of the thread, however small, as an extra- 

 neous body, and therefore do not perfectly return to their natural state 

 of feeling and action, until the ligature be removed. 



" It is well known that metallic substances lie in the living struc- 

 ture, without exciting in it any irritation, or efibrts to expel them ; I 

 therefore conceived that a ligature made of leaden wire might be 

 employed with many advantages. I accordingly made the experiment 

 of tying both the carotid arteries of a dog with a filament of lead. I 

 cut off the ends of the leaden wire close to the artery, and healed the 

 wounds over them. I killed the animal some weeks afterwards, and 

 found both the vessels obliterated. One of the ligatures remained on 

 the artery, and the other had been removed by interstitial absorption, 

 and lay on the side of the vessel. Both were inclosed in a capsule of 

 transparent cellular membrane ; no lymph had been shed, except what 

 was sufficient for the consolidation of the divided coats of the arteries. 

 As the presence of the lead had not created irritation, lymph was not 

 required to limit or arrest inflammation." 



(The appearances were represented in accompanying drawings.) 



*' I afterwards tied both the jugular veins of the rabbit in the same 

 manner. The animal died in two days of apoplexy, as was expected ; 

 but no appearance of inflammation existed around the veins, and both 

 ligatures remained on the vessels. These experiments were made 

 before Dr. Dieffenbach employed the metallic ligature for closing the 

 fissures of the palate. A considerable improvement has since been 

 made by Mr. Weiss, by substituting soft metal for the leaden wire. 

 Weiss's ligature is so flexible, that it admits of being tied in a knot. I 

 have since had a silver needle, and also a steel one made, for receiving 

 the end of the metallic ligature, and passing it under an artery." 



Several cases are recorded of even large arteries being broken, in 

 lacerated wounds, without yielding any haemorrhage. In experiments 

 to discover the reason of this, it was found that, by pulling the artery 

 slowly until it gave way, it yielded a few drops of blood, after which 

 no more issued ; and on examining the artery immediately after the 

 experiment, the matter was fully explained ; it was found that the 

 middle and internal coats had first been broken. They presented an 

 inverted edge or burr within the tube ; and the cellular coat, as it 

 admits of more extension, had been drawn out into the form of an 

 elongated cone before it gave way ; therefore the hole left at the bottom 

 of the cone was very minute. There seemed to be no disposition in 

 the cone of cellular substance to fall back into the cylindric form ; but 



A 



