ROARING IN HORSES. 29 



by Trendelenburg for human surgery, and 

 intended to prevent the entrance of foreign 

 bodies into the trachea (fig. 8). It is a long 

 tracheotomy tube, the flattened surface or 



Fig. 6. — Spring hooks. 



pavilion of which is provided with a cap to 

 protect the outer orifice of the canula ; the 

 tube is surrounded on its external surface 

 with an india-rubber covering which fits very 

 tightly except in the middle, at which point, 

 when in position and in use, it forms a sort 



