PRACTICAL APPLICATIONS 415 



respiratory and cardiac centres at the floor of the fourth ventricle. 

 Another method is to inject small quantities of the fluid directly 

 into the spinal cord by means of a needle introduced between the 

 sixth and seventh cervical vertebrae. This procedure would 

 appear to be dangerous, but this is said not to be the case. 

 Lastly, the simplest method of all is to perform lumbar puncture, 

 draw off some of the cerebro-spinal fluid, and replace it with 

 serum, just as in the process of spinal anaesthesia. 



Ransom and Meyer have advocated the direct application of 

 antitoxin to the nerves supplying the region in which the wound 

 is situated, the idea being, of course, to intercept any further 

 access of toxin to the brain and cord. The nerves are exposed 

 by operation as near to their origin as possible, and infiltrated 

 with serum by means of a hypodermic syringe. 



Analogy with other diseases would fully justify the use of 

 vaccine in chronic tetanus. Its preparation would present some 

 difficulties, owing to the heat-resisting power of the spores. 



Syphilis. 



Little is known definitely concerning the mode of cure or of the 

 type of immunity of syphilis. It used to be regarded as one of 

 the diseases which are followed by practically complete immunity 

 of long duration, but Neisser has brought forward some evidence 

 for thinking that this is not the case, and that it only lasts as 

 long as the disease itself i.e., as soon as it is completely eradicated 

 the patient is again susceptible. Nothing is known as to the 

 toxins of syphilis, and, as regards the method of cure, the only 

 point worth mentioning is the fact that spirochaetes which have 

 been ingested by the leucocytes can be made out occasionally. 

 They stain badly, and are doubtless on the way to complete 

 absorption. The fact that the organism cannot be obtained in 

 pure culture renders researches with regard to the opsonic and 

 bacteriolytic action of the serum very difficult. Indirect researches 

 by means of the deviation of complement constituting the 

 Wassermann reaction, a special method of application of the 

 Bordet-Gengou reaction have led to results of great interest 

 which have recently attracted much attention. 



The first necessity was, of course, the preparation of an antigen, 

 and for this purpose Wassermann made use of the internal organs 

 of a syphilitic fretus, which were swarming with spirochaetes. In 



