244 MICROBIOLOGY 



of the malleasa is poured into a glass test tube of three to four 

 millimeters in diameter and fifteen centimeters long, so that the 

 liquid in the tube is about three centimeters in height. Then about 

 the same quantity of the blood serum from the suspected horse is 

 taken in a Pasteur pipette which is introduced into the tube contain- 

 ing the malleasa in such a manner that the point of the Pasteur 

 pipette reaches the bottom of the tube. Not until then is the serum 

 allowed to pour very slowly under the malleasa. Inasmuch as the 

 serum has a higher specific gravity it remains at the bottom, while 

 the malleasa is forced up. The free end of the pipette is then cov- 

 ered with the finger and the pipette is carefully taken out, so that 

 the serum is not mixed with the malleasa. Such a mixing should 

 also be avoided during the introduction of the pipette into the serum. 

 The two solutions must only come in contact at one point and then 

 the reaction will be very marked. 



"In case of a positive reaction, that is, when the serum is ob- 

 tained from a horse affected with glanders, a ring of white cloudiness 

 develops at the point of contact of the two clear solutions, as a 

 result of the precipitin formation, which is particularly marked in 

 good daylight when the tube is placed in front of a window against 

 some dark object. According to the duration of the disease, the 

 white ring develops at various times and in varying intensity. In 

 severe and chronic cases of glanders the serum produces the ring 

 immediately; in slight affections when the lesions are not very 

 marked in the animal, the precipitation reaction appears in from 

 five to fifteen minutes." 



Malleasa. Malleasa is prepared by dissolving the glan- 

 ders bacteria that appear on a two day old agar culture with 

 an 8% antiformin solution using about 10 cc. for each agar 

 culture. 10 The antiformin dissolves the glanders growth in 

 about two hours. A sufficient amount of culture should be 

 added to require about two hours to dissolve the bacteria. 

 The solution is strongly alkaline but should be neutralized by 

 adding a 5% solution pf sulphuric acid. It is then filtered 

 first through filter paper and then a Berkefeld filter in order 

 that the solution may be homogeneous. To this solution 



10 The antiformin is the patented name of a disinfectant made 

 by adding sodium hydrate to a solution of sodium hypochloride. It 

 can be obtained in the market. Its activity seems to be due to an 

 intense oxidation. 



