INTRODUCTION 1 3 



pushed in very slowly so that one-fourth of the amount in the 

 syringe is forced out in ten minutes. While the injection is 

 being made the limb should be gently massaged by pinching 

 and rubbing from the foot toward the body. This facilitates 

 the flow of the liquid in the lymph-vessels. In this manner the 

 lymphatics of each limb are filled. The author has been able to 

 fill the left thoracic duct by continuing the injection for about 

 twenty minutes in the palm of the left paw. The lymphatics 

 of the head and neck may be injected in a similar manner by 

 inserting the cannula beneath the skin on the tip of the ear, 

 the top of the tongue, the tip of the nose, and the lips. 



In order to inject the lacteals the abdominal cavity must be 

 opened, and the cannula inserted very obliquely into the wall 

 of the small intestine so that its point is between the mucous 

 and muscular coats. The half-filled syringe being attached, 

 very gentle pressure should then be exerted on the plunger, 

 until the injecting solution appears in the lacteals. To inject 

 all the lacteals it is necessary to insert the cannula into the wall 

 of the intestine at a dozen different places. To fill the thoracic 

 duct, injection may be made into the large lymphatic gland lying 

 at the point where the covering blood-vessels of the mesentery 

 meet. The best solution for injecting the thoracic duct is made 

 by dissolving 7 gm. of gelatin in a warm Berlin blue solution (4 

 gm. of Berlin blue to 100 c.c. water). This should be filtered 

 through a single layer of absorbent cotton and then injected, 

 while still quite warm. In all cases injections to fill the lym- 

 phatics must be warm and must be pushed in very slowly. 

 These lymphatic injections are best preserved by injecting 

 the trachea and intestine with 95% alcohol and immersing the 

 cat in a jar of 70% alcohol. Professor Gage makes a beautiful 

 demonstration of the lymphatic system by feeding — a cat that 

 has been starved 18 to 24 hours some butter colored — with 

 Sudan III. After three or four hours the cat is killed and dis- 

 sected. The lymphatics stand out in red. 



