Dr. Buchanan on the White <yr Opaque Serum of the Blood. 229 



few ounces of blood, was easilj prevailed upon to submit to the follow- 

 ing rogimon and treatment. He had no breakfast, and at four o'clock 

 had for dinner one pound of beef-steak, half-a-pound of bread, sixteen 

 liquid ounces of brown soup, and half-a-bottle of porter. Three ounces 

 of blood were then taken from a vein in the arm at three diflferent 

 periods ; the first time, half-an-hour after the meal ; the second time, 

 an hour and forty minutes after it ; and the last time, next morning 

 at eight o'clock, or sixteen hours after the meal, no food having been 

 taken in the interval. The blood as it issued from the vein had the 

 usual appearance, and the serum which separated from it was about 

 the same in quantity each time. The first time the serum was whitish 

 and turbid ; the second time it was like whey ; while the third time it 

 was perfectly limpid. The crassamentum on the two first occasions 

 exhibited nothing peculiar, while on the last it was covered with a 

 transparent fibrinous crust beautifully interspersed with white dots, 

 which led the medical friend, who assisted me in these investigations 

 to compare it to a precious stone. 



As it might be supposed that this young man's blood was white be- 

 fore he took dinner, the two following trials were made to obviate that 

 objection. 



A vigorous man of about 35 years of age, after fasting 19 hours, had 

 for dinner, twenty ounces of beef-steak, sixteen liquid ounces of brown 

 soup, and eight ounces of bread. He was bled immediately before his 

 meal, and three times after it, two ounces of blood being taken away 

 each time. The serum obtained from the first bleeding before the 

 meal was perfectly limpid ; the serum from the second bleeding, three 

 hours and fifteen minutes after the meal, was turbid ; the serum from 

 the third bleeding, eight hours and fifteen minutes after the meal, was 

 still thicker ; while that from the last bleeding eighteen hours after 

 the meal, was again quite limpid, although some supper had been eaten 

 in the interval. 



The young man first mentioned, after fasting eighteen hours, dined 

 upon sixteen ounces of brown soup, four ounces of bread, eight ounces 

 of potatoes, twenty ounces of beef-steak, and sixteen ounces of London 

 porter, and fasted eighteen hours after the meaL He had blood taken 

 from his arm four times to the extent of two ounces each time. The 

 serum of the blood first taken, immediately before the meal, was of an 

 amber yellow and quite transparent ; the serum from the second bleed- 

 ing, two hours and ten minutes after the meal, was turbid ; the serum 

 from the third bleeding, eight hours after the meal, was exactly of the 

 colour of water gruel and quite opaque ; the serum of the blood last 

 taken, eighteen hours after the meal, was still turbid, its limpidity not 

 having been, as after his usual fare, restored by an eighteen-hours' fast. 



In neither of the two last cases did the blood, as it issued from the 

 arm, present white streaks or any thing else unusual. The crassa- 

 mentum of the blood drawn before the meal, was in both cases of the 



No. 10. 3 



