( 78 ) 



Experiments on the Velocity of the Circulatory Motion of the 

 Blood, and on the quickness with zvhich the secretions ai'C per- 

 formed. By E. He ring, Professor at the Veterinary School 

 of Stuttgard *. 



These experiments, to the number of eighteen, were made on 

 horses. There was injected, or rather infused, into the jugular 

 vein, a solution of hydrocyanate of potash and iron. To intro- 

 duce the liquid, there was employed a glass-tube, of the size of 

 a writing quill, capable of being closed by means of a stop-cock, 

 and surmounted by a brass funnel, holding two ounces of li- 

 quid. The tube being introduced into the vein, the funnel was 

 filled, and the cock opened, to be shut again the moment the 

 liquid had passed into the vein. In this manner the access of 

 air was prevented. After some time, a vein was opened in ano- 

 ther part of the body, and the blood examined by chemical re- 

 agents. The animals were killed some time after, and the traces 

 of the liquid introduced was sought for in the secreting organs 

 and their products. The second series of experiments is taform 

 the subject of a separate memoir. 



As a re-agent for discovering the hydrocyanate of iron in the 

 blood, the author preferred the sulphate of iron to the sulphate 

 of copper, or the hydro-chlorate of iron. To form a blue preci- 

 pitate with this salt, it was only necessary to add a little hydro- 

 chloric acid. The hydrocyanate of potash and iron was also re- 

 cognised, although existing only in the proportion of 1 to 

 20,000 in the serum of the blood. The small quantities of hy- 

 drocyanate not being discoverable in the coloured blood, it was 

 necessary to let it rest from twenty-four to forty-eight hours to 

 have a clear and limpid serum. Some drops were let fall on 

 white paper, and there were afterwards added a few dr6ps of a 

 solution of sulphate of iron (1 gr. in 3 ounces of distilled wa- 

 ter) ; a drop of concentrated hydrochloric acid, which was add- 

 ed in the last place, instantly betrayed the presence of the hy- 

 drocyanate. This procedure is equally appHcable to the solid 

 parts that are submitted to examination. 



• Zeitschrift fur Physiologic, t. ii. p. 85. 



