108 CIRCULATING FLUIDS: 



dissolved the corpuscles, (possibly through the iafluence of the 

 amraoniacal salts.) 



Pure urea, prepared artificially, induced no change in the 

 colour, but dissolved the corpuscles, with the exception of the 

 nuclei and a few fragments of the capsules. 



The action of putrid blood and serum has been already 

 noticed. 



Human blood does not appear to be influenced by admixture 

 with the blood of birds or frogs. 



The bile of man, quadrupeds, birds, fishes, and amphibia, 

 exerts an active soluble influence upon the corpuscles. In 

 some observations on frog's blood, Hiinefeld noticed that the 

 capsules were immediately dissolved, and that the nuclei re- 

 mained unchanged for some time, but ultimately broke up into 

 minute granules and disappeared. 



The eflects produced by coneia appear, from Hiiuefeld^s ob- 

 servation, to be very singular. 



Coneine, either in a state of solution or vapour, reduces the 

 blood to a dirty red greasy mass, which, under the microscope, 

 resembles dark melted wax, and in which no corpuscles can be 

 detected. If diluted blood be treated with a little coneine, it 

 remains fluid, but, after a short time, becomes discoloured, and 

 throws down a brown sediment. The blood of a rabbit, poi- 

 soned with coneine, exhibited no peculiarity. 



Arsenic acid produces no material efi'ect upon the blood, nor 

 could Hiinefeld detect any alteration in the corpuscles of a frog 

 destroyed by this agent. 



On passing hydrocyanic acid, in a state of vapour, into the 

 blood of a pig, the colour became more vivid, and the corpuscles 

 remained uninjured for a very considerable time. A large 

 quantity of blood, which was treated in a similar manner, gave 

 oS" a strong odour of the acid after the lapse of a year and a 

 half, and did not exhibit any symptoms of putrefaction. No 

 change could be observed in the blood of a rabbit poisoned 

 with this agent. 



Chlorate of potash does not produce any apparent effect for 

 the first few minutes ; subsequently, however, the blood assumes 

 a brighter red tint, which ultimately passes into a brown. An 

 ounce of fresh human blood was mixed with eight grains of 

 chlorate of potash. Just at first the colour became rather 



