160 The Diseases of Animals 



the heart again. Arteries have thick elastic walls, that 

 throb with the beating of the heart, and the blood is 

 always under considerable pressure. If an artery is cut 

 the blood is bright scarlet in color and flows with force, 

 coming in a full spinning stream. If a vein is cut 

 the blood is dark in color and simply wells out of the 

 wound with no force. In stopping a severe hemor- 

 rhage, it is necessary to know whether an artery or 

 a vein is severed. If an artery, the end of the blood- 

 vessel toward the heart must be treated, as the blood 

 comes from the heart. If a vein is cut, the end of 

 the blood-vessel away from the heart must be treated, 

 as the blood is flowing from the extremity toward the 

 heart. If the hemorrhage is from a large blood-vessel, 

 the best way to stop it is to find the cut end of the 

 vessel and ligate, or tie it. This can be done by get- 

 ting hold of the cut end with the fingers, pulling the 

 blood-vessel out a little and tying it tightly with silk 

 or linen thread or any other that can be obtained, 

 provided it is clean. The thread should be tied with 

 a "'surgeon's knot," as this does not slip. Fig. 38. 

 Another practicable method of stop- 

 ping hemorrhage from large blood- 

 vessels is to sear with a hot iron; 

 but this is severe treatment, and 

 should be used only when abso- 



lig. 38. Sureeon's knot. , . , ti. ^ ■,-, 



lately necessary. If carefully ap- 

 plied to the blood-vessel itself, however, there is com- 

 paratively little pain and the treatment is effective. 



For ordinary, and even for severe wounds, nature 

 has an admirable way of stopping hemorrhage. The 



