190 APPENDIX 



spinal fluid contained syphilis antibody. As in 

 most such tests, only a positive result determines ; 

 a negative result does not necessarily exclude the 

 presence of syphilitic infection. 



While the above exposition will serve to fix the 

 general plan of the test in the mind of the reader, 

 we must at once say that the mode of action is not 

 as simple as Wassermann first believed. Before 

 going into this phase of the subject, it will be 

 advisable to present a description of the technique 

 of the test. 



For carrying out the test the following materials 

 are required: 



(i)" Antigen," i.e. fluid containing syphilis ma- 

 terial. This is comparable to the pure culture of 

 typhoid in the test described above. 



(2) Serum or cerebrospinal fluid from the patient 

 to be examined. 



(3) Sheep blood cells. 



(4) Haemolytic antibody, i.e. inactivated serum 

 of a rabbit immunized against sheep blood cells. 



(5) Complement, i.e. fresh normal serum from a 

 guinea-pig. 



For the syphilis antigen it is best to use the 

 organs of a syphilitic foetus, i.e. one dead of heredi- 

 tary syphilis, as these tissues are particularly rich 

 in spirochaetes. The organs are chopped up and 

 macerated in a clean vessel in a mixture composed 

 of water, 1000; NaCl, 8.5; carbolic acid, 5.0; one 

 part of the tissue to four of the fluid. The mixture 

 is shaken in a shaking apparatus for twenty hours ; 



