268 GENERAL THERAPEUTICS FOR VETERINARIANS 



causes at first, in consequence of irritation of the peripheral vaso- 

 motor centres (Lenaschew, Pliigers Archiv., vol. 26), a contraction 

 of the cutaneous vessels with anaemia of the skin, which drives the 

 blood to the interior and also increases the blood-pressure, the 

 activity of the heart and the internal temperature. With the 

 occurrence of the reaction in the skin, contrary effects are pro- 

 duced. The blood-vessels dilate, the blood flows from the centre 

 to the periphery, and blood-pressure, heart activity, pulse fre- 

 quency and internal temperature decrease. It is therefore pos- 

 sible to act with hydrotherapy upon every single factor of the circu- 

 lation: upon the lumen and tension of the blood-vessels, upon the 

 heart, upon the blood-pressure, upon the blood distribution and 

 upon the blood heat. Water is consequently a valuable remedy 

 in all conditions of inflammation and congestion and in general 

 febrile diseases. It is also a derivative remedy, particularly on 

 account of its regulating influence upon blood distribution. Inter- 

 esting investigations have been made by Schiiller (Deutsches 

 Archiv. fiir Klin. Medizin, vol. 14) concerning the derivative effect 

 of water upon the deeply situated organs, which are of therapeutic 

 importance, especially in inflammation of the brain. In trephined 

 rabbits, constriction of the vessels of the pia and contraction of the 

 brain were observed after the application of warm compresses to the 

 skin, while the employment of cold dressings on the skin or a cold 

 bath caused a dilation of the vessels of the pia. The same action 

 apparently extends to the spinal cord, the lungs and the other vis- 

 cera. These experimentally established facts justify scientifically 

 the hydropathic derivation which has been hitherto practised 

 empirically, especially in inflammation of the brain, pneumonia, 

 pleuritis and peritonitis. Finally, since cold water also increases 

 metabolism, as is shown by the increased elimination of carbon 

 dioxide and the increased absorption of oxygen demonstrated in 

 animals experimentally by Rohrig and Zuntz, the resorbent effects 

 of external applications of water in connection with the stimula- 

 tion of the circulation are readily understood. 



3. The nervous system is affected in different ways, accord- 



