AND ANIMAL LIFE. 27 



in congestion when the capillary and larger ves- 

 sels have their action increased, whether by heat, 

 galvanism, or stimulants ; and these parts being, 

 in some measure, disburdened of their own in- 

 dividual load, are prepared to take off a por- 

 tion from the lungs and heart ; or the excited ac- 

 tion of their vessels is communicated to those or- 

 gans ; and from this cause, or rather from the 

 combination of the two, the respiratory function 

 speedily regains its ordinary degree of activity, 

 and re-establishes throughout the system the ef- 

 fects of its invigorated energy.* 



XXXII. It is imagined by some authors of 

 distinction, that an explanation founded on phy- 

 sical principles is insufficient to account for the 

 phenomena : they are disposed to attribute the 

 beneficial consequences to nervous influence or 

 connection ; but as they have not yet favoured 

 the world with reasons, beyond mere surmises or 

 hypotheses, we must adhere to that explanation 

 which is strengthened by so many obvious ef- 

 fects in close relation to the cause assigned, that 

 it is almost impossible to observe one without 

 becoming acquainted with the other. 



* Dr KELLIE, some years ago, proposed the attempt to 

 stop the cold stage of intermittent fever, by applying the 

 tourniquet to the inferior extremities, and it has certainly 

 been successful. The ancients also employed ligatures for 

 the same object, and in a similar manner. The former was 

 the suggestion of physiological principles, the latter of empiri- 

 cism. 



