130 GLANDERS 
Dilution of Serum Panount: satan Diluted | Amount cf Test Fluid Dilution 
1-40 1.2 ce. | 3 ee. 1-100 
1-40 0.6 3 1-200 
1-40 0.405 3 1-300 
1-40 0.3 3 1-400 
1-40 0.24 3 1-500 
1-40 0.195 | 3 1-600 
1-40 0.15 | 3 1-800 
1-40 0.12 3 1-1,000 
1-40 0.105 3 1-1,200 
1-40 0.09 3 1-1,500 
1-40 0.06 3 12,000 
1-40 0.03 3 1-4,000 
1-40 0.015 3 1-8,000 
Where dilutions greater than 1-1000 are made, a serum diluted 1-80 
may be used to better advantage, unless the pipette employed is very 
finely graduated. In this case the amount of diluted serum for a 
certain dilution must be double that indicated in the table. 
The mixture thus prepared is placed in an incubator at 37° C. for 
24-30 hours. A temperature higher than 37° C. interferes with the 
agglutination. 
The reaction consists of a layer of the agglutinated bacteria cover- 
ing the entire convexity at the bottom of the tube. This film-like 
sediment may become so dense that it rolls in at the periphery. The 
supernatant fluid becomes clear in the lower dilutions, but in the 
higher ones the clarification may not be complete, showing that all 
the bacteria have not become agglutinated. This is further evidenced 
by the fact that the layer is less dense in the higher dilutions. The 
reaction may begin in six hours, but cannot be considered complete 
until 24 to 36 hours have elapsed. If no reaction appears in 24 hours 
it cannot be considered negative, as it may occur in from 30 to 40 
hours after setting. Often, however, a reaction appears in less than 
24 hours. 
After the agglutination is completed, further standing produced no 
visible change in the test fluid. 
A negative result shows a small round concentrated spot of sedi- 
ment in the center of the convexity at the bottom of the tube, the test 
fluid remaining apparently unchanged even after several weeks. 
Animals whose blood serum agglutinates in dilutions of 1-500 are 
