HO LABORATORY GUIDE IN BACTERIOLOGY 



b) Wash with mercuric chlorid solution and alcohol. 



c) Inoculate intravenously with 0.5 c.c. of a 24-hour- 

 old milk-culture. 



d) After the culture has been fully distributed in the 

 circulation, which takes at the most 3 minutes, kill the 

 rabbit by a quick blow on the back of the neck. 



e) Put the rabbit in a warm place — say, on top of the 

 thermostat — for 18 hours, or from 6 to 8 hours inside of 

 the thermostat. 



/) After this time has elapsed, perform an autopsy. 

 Note the crackling, on pressure, over the axillary or 

 inguinal regions. The rabbit is swollen to a great 

 extent. Skin the animal carefully, without opening the 

 abdominal cavity; then quickly puncture the abdominal 

 wall and bring a flame to the opening. Note that the 

 escaping gas will burn with a blue flame. What is this 

 gas? Also note the disorganized condition of the liver, 

 spleen, and kidney. 



g) Make capsule stains from the heart's blood or 

 organs by Welch's method (modified) . The modification 

 of Welch's method is as follows: Proceed in the manner 

 indicated on p. 77 and, after washing the acetic acid off 

 with the stain (carbol-fuchsin or gentian- violet) , dry vsath 

 filter paper, heat the specimen for 5 to 10 seconds before 

 washing ofi with the salt solution. Then proceed as 

 before. 



6. Special study F. — Staining of spores of B. tetani 

 and B. oedemalis maligni from 3-day-old glucose-agar- 

 cultures (see p. 98). 



7. Special Study G. — Inoculation of a white mouse 

 or guinea-pig with B. tetani or its toxin (o.oi c.c.) in the 

 hind-leg or over the root of the tail (if a mouse). Note 



