132 CLINICAL BACTERIOLOGY AND 



Arloing's Double Vaccine Method. 



Here two vaccines of varying degrees of virulence are 

 used, the first being given to prepare the system for the 

 second and more virulent dose. 



They are prepared as follows : The diseased muscle is 

 dried in the sterilizer (dry-air) at a temperature of 35° C, 

 powdered, mixed with water to form a paste, and spread 

 on a glass plate, exactly the same as in Kitt's method. 



It is then placed in a thermostat for six hours, and main- 

 tained at a temperature of 103° C. 



The dried powder is now put in a sterile mortar, 

 ground down finely, placed in a sterile stock vaccine bottle, 

 with rubber cap or glass stopper, and labelled "Vaccine 

 No. 1." 



Vaccine No. 2 should be treated in exactly the same way, 

 only instead of being subjected to a temperature of 103° C, 

 a temperature of 95° C. is required. 



The dose of each vaccine is 1 centigramme. 



No. 2 vaccine should be administered within ten days 

 of No. 1. 



The vaccine may be dissolved in normal saline solution 

 to which is added 05 per cent, of lysol, and used as a liquid 

 injection; or several layers of thread may be plaited 

 together to form a single cord. Several of these should be 

 steeped in the vaccine emulsion, each cord then constituting 

 one dose. 



When an animal is already infected, the vaccine may not 

 be effectual — in fact, during the process of vaccination they 

 are liable to bruise themselves, and often thereby determine 

 the disease. In the writer's experience, complete immunity 

 is not arrived at until the lapse of three weeks, after which 

 period they are usually safe for twelve months. To reduce 

 the risks of bruising during inoculation by the cord 

 method, we find, if there are a number of animals to 

 be inoculated, they can be speedily done if placed in a 

 small house, so that they cannot run about. The operator 

 should catch the tail of an animal so sardined between its 



