Dr. Buchanan an the White or Opaque Serum of the Blood. 233 



preceded by a pain in his head for two or three days; that his 

 bleeding continued till he had lost about two pounds of blood, and 

 then stopt ; and that the serum of his blood was as white as milk. 

 That at ten o'clock the same night, the hemorrhage returned, and he 

 lost a considerable quantity ; nevertheless, it was thought proper to 

 take sixteen ounces of blood from his arm, during which evacuation 

 he fainted, but his bleeding at the nose stopt. That the serum of this 

 last blood was likewise very white. That on the 25th, in the morning, 

 he again complained of a pain in his head, and about ten o'clock his 

 nose began to bleed again ; but the serum now appeared no whiter 

 than whey. That he continued to lose blood during most part of the 

 night, so that it was supposed he could not lose less than two or 

 three pounds, the serum all this time being a little whitish, but so 

 little, that the bottom of the vessel in which it stood could now be seen 

 through it That his bleeding returned repeatedly, till the third of 

 October, when it entirely stopt, the serum having become more tran- 

 sparent towards the last." 



Now, as it can scarcely be supposed that this man had gorged him- 

 self with food to such an extent before his illness, that his blood con- 

 tinued white for ten days afterwards, and as a spare diet would cer- 

 tainly be enjoined for so severe a complaint, we must conclude that 

 the process of digestion in the blood-vessels was, in this case, preter- 

 naturally retarded, or in a state of disease. I have no doubt that 

 hereafter, when the normal changes produced by digestion upon the 

 blood are better understood, light may be thrown upon the nature 

 of some diseases of nutrition, by administering certain articles of 

 food, and examining the condition of the blood so many hours after- 

 wards. 



It is a fact of great interest, which has been established by various 

 observers, that in diabetes, the serum of the blood often presents the 

 milky opacity in great intensity. This is no more than might have 

 been anticipated from the very large quantity of food taken by those 

 labouring under that disease, which is often three or four times 

 greater than is consumed by persons in health : for if the stomach 

 act upon the food in the usual way, it cannot but happen that the 

 blood will be loaded with white particles. Many pathologists indeed 

 suppose, that a deranged digestion in the stomach is the fundamental 

 part of diabetes. But the fact here mentioned seems to me, in some 

 measure, inconsistent with that theory ; for it shows that the food in 

 diabetes undergoes the usual changes in the stomach, and is introduced 

 into the blood in the usual form, so far as sensible characters enable 

 us to judge. We may therefore be allowed to conjecture, that the 

 essential derangement in diabetes is not a derangement of the primary 

 digestion in the stomach, but of the secondary digestion in the blood- 

 vessels, by which the unassimilated nutriment no longer undergoes 

 the same series of changes as in the healthy state. 



