METHOD OF MAKING INTRAVENOUS INOCULATION 



59 



6. Pick up the skin just above and in the middle of the space be- 

 tween the shoulder and the tip of the upper end of the sternum just 

 above and about in the center of the area where a clavicle in the human 

 would be situated. With sharp small scissors incise the skin for about 

 one-third of an inch. Separate the subcutaneous tissue gently with 

 forceps; a large vein at once comes in view (Fig. 29). Gently dissect 

 it free for about one-fourth of an inch. 



FIG. 30. INTRAVENOUS INOCULATION OF A GUINEA-PIG. 



The vein is steadied by a pair of fine forceps and the injection given through a 

 small needle. The incision here shown is larger than actually required in practice; 

 the vein is also smaller than normal, as the animal was dead for a few hours prior to 

 making the illustration. 



7. Pick up the vein with a pair of fine forceps, insert the needle 

 of the syringe gently in the long axis of the vein and slowly inject the 

 fluid (Fig. 30). 



8. Withdraw the needle and apply firm pressure with a wad of clean 

 gauze or cotton. It is not necessary to tie off the vein. A stitch may 

 be inserted to close the skin wound and flexible collodion applied. 



