64 Dr. Buchanan on the State of the Blood after talcing Food. 



described, or by analogous processes to be hereafter mentionod. This 

 however is only done for convenience, and without prejudging the 

 questions as to the origin of tho mattor so designated, and its relations 

 to the white matter which gives the milkiness to the blood. 



Eggs. — On tho 20th of May, F. had for dinner six eggs, which were eaten without 

 any other accompaniment than a little salt. He was bled at two and at four hours 

 after the meal. The serum was small in quantity in both cups, which were very 

 full, and with the coagulum adhering, by means of froth, to the edges, so that the 

 whole serum lay on the surface of the coagulum. It was deeply tinged red. 



The serum from the blood first drawn was kept two days, that the red matter of 

 the blood might subside from it. During that time it threw up a cream spontane- 

 ously. On filtering it, the white matter and a little oil were left on the filtering 

 paper: the latter being shown, as formerly, by drying the paper. The filtered liquid 

 was quite transparent, but on adding salt to supersaturation, a greyish sublimate 

 separated, showing that the salt acted as a precipitant, if indeed that name may be 

 applied to an agent separating a matter which swims on the surface. 



The serum from the blood last drawn threw up no cream, although kept the same 

 time as the other specimen. On adding salt in the usual way, a sublimate separated 

 so abundant as to be equal to about one-fourth of the whole liquid in volume. It 

 was loose and flocculent; greyish, like chewed meat; or more strikingly still — 

 (although the physician only can appreciate the comparison) — like the character- 

 istic discharge from the bowels in dysentery. It continued several days at the top, 

 with no tendency to subside. It was then skimmed off, and a part of it left behind 

 subsided probably from the agitation. The sediment thus produced was completely 

 redissolved on adding water, the solution being then quite transparent, but on 

 again saturating with salt becoming turbid. 



The coagulum was, in both cups, natural. 



Casein. — On the 29th of May, G. having taken no breakfast, had at 1 1 a.m. a Scotch 

 pint of curds, (two English quarts nearly.) He was bled at two, and at four hours 

 after the meal. The serum in both cups was very abundant, being after thirty hours 

 about equal in volume to three-fourths of the whole blood drawn. That in the first 

 cup was the most abundant, and the corresponding coagulum had a thick buffy 

 coat. The other coagulum had only a trace of a paler fibrinous crust. 



The serum in both instances was turbid ; but that was owing to a minute quantity 

 of red colouring matter, which, subsiding in six hours, left both liquids beautifully 

 transparent, that from the blood first drawn having a greenish, while the other 

 inclined to a yellow tint. Salt added to supersaturation gave an abundant precipi- 

 tate, which partly rose to the surface, buoyed up by minute air-bells, but was 

 chiefly diffused through the liquid in voluminous flocks, and at length the whole 

 subsided to the bottom. 



The transparent liquid placed under the microscope was observed to contain 

 some minute entozoa (vibriones), although it was quite fresh. This was forty-six 

 hours after the blood had been drawn, the weather being coldish at the time. I 

 once before saw the same animalcules in blood taken from a man after a fast of 

 sixteen hours. They were elongated, and of very rapid movement, and not accom- 

 panied by any of the globular and elliptical infusoria which commonly show them- 

 selves first in organic liquids undergoing decomposition. 



Thinking that other salts naturally contained in the serum, and 

 therefore not likely to interfere with its chemical equilibrium, might 

 causo a precipitate like common salt, I tried phosphate of soda, but 

 on adding it to supersaturation it did not at all affect the limpidity of 

 the serum ; and on afterwards adding common salt, tho usual effect 



