ACTION ON BLOOD. 43 



beats of the heart more intense; respirations 12; urine less 

 abundant and less limpid. Tlie functions now began to return 

 little by little to their normal state. In almost every case whicli 

 they experimented on, the history was exactly the same. In 

 these experiments we note a steady diminution of the respira- 

 tions, temperature, pulse, and intensity of cardiac beats, with 

 increase of the amount of urine, these effects reaching their 

 maximum in 24 to 36 hours, and then gradually disappearing. 

 The effects of digitalis upon other mammals and man seem, 

 <)cvteris paribus, to correspond closely to those on horses, except 

 that in the latter, and in herbivora generally, there is no 

 vomiting. 



Having given this description of its general action, I will 

 now consider its action on various organs more in detail. 



On the Blood. — Majendie* states that decoction of digitalis, 

 when mixed witli blood, prevents its coagulation, and Thackrah,t 

 that it suspended coagulation, and the clot at length resulting 

 was black. Davy says that 5ss. of extract of digitalis in jj of 

 water, added to ^'\i of blood as it flowed from the arm, gave it 

 the consistence of paste; after 36 hours it appeared much the 

 same ; on the following day, the lower part was more viscid, as 

 if from subsidence of fibrin — it was coagulated on dilution 

 with water. It is impossible to draw any definite conclusion 

 from these statements, as to whether it has any specific action 

 on the blood or not, as the prevention or suspension of coagula- 

 tion in the first two cases may have been merely from dilution, 

 and the black colour of the clot may be due to the colourino- 

 matter of the decoction. In the third case, the prevention of 

 coagulation seems due to the viscosity induced by mixing the 

 sticky extract with the blood, and as soon as this mechanical 

 effect was removed by dilution, the blood coagulated. Orfilaf 

 found, that after poisoning dogs with watery extract of digitalis, 

 the blood was fluid in all the five cases in which he mentions 

 its condition. He concludes that " alcoholic (resinous) extract 

 appears to act especially on the heart or blood, since this fluid is 

 constantly found coagulated immediately after death, whenever 



* Quoted bv Lancet, 1837. 



t Orjilas Toxicologtf, by Waller, 1817, vol. ii, p. 231. 



