The question lias arisen in the course of the discussion as to whether this coccus is the causa vera of cerebro-spinal meningitis. As far as one can see at present, there can be httle or no d()ul)tof this. It is true that cMcci are a dangeroiiiM and ehisive race, but this species is found so constajitly in the cerebro-spinal fluid of cases of cerebro-spinal meningitis, that most workers agree that it must be the real begetter and originator of til is disease. A fact which seems to me to carr- a good deal of vveiglit in this connection is, that when a particular strain or variety of the meningococcus is found in a particular epidemic, the same strain or variety is also found in the contacts. Some one has said " that no truth lasts longer than fifteen years," but I dare to prophesy that the life of this coccus will l)e longer.
Major Atkinson told us that in regard to the relation of the meningococcus to this disease, Koch's three postulates have been fully satisfied. What about the third ? At present the only way of setting up the disease in healthy animals by means of a pure culture is by injecting it into the cerebro-spinal canal, but many other organisms, if injected the same way, give rise to a simihn- inflammation. Until the disease is brought about by implanting the meningococcus on the nnicous membrane of the pharynx, it can hardly be said that all three of Koch's demands have been fully answered in the affirmative.
In regard to vaccination against cerebro-spinal fever by the injection of the meningococcus, little has been done up to the present. Dr. Penfold, of the Lister Institute, carried out a series of inoculations at Salis- bury, during the epidemic which occurred there a year ago, with what is Lcported to have been results suggestive of success. Lately, another opportunity occuj-red of testing the benefit of vaccination in a camp of Colonial troops, but Colonel Gordon informs me that although the epidemic ceased, there was no proof that this was due to the vaccine, as all the soldiers in canip were inoculated. There were no controls by which to test the results. On the whole, I think that the prospect of prophylactic inoculation against cerebro-spinal fever is favourable.
Lastly, as regards serunj therapy. According to Colonel Gordon there are four strains of the meningococcus at present in England causing epidemics of cerebro-spinal fever. At one place an epidemic is caused by one strain, at another place by a difterent one. It then is necessary, in order to ^et good results, that a polyvalent serum got from horses,
