OUTLOOK. 687 



shows very clearly that Ehrlich is right in his conception of the production 

 of toxines by the cells. Wassermann and Takaki 1 carried out the fol- 

 lowing experiment. They triturated the spinal cords and brains of 

 normal guinea pigs with a physiological salt solution. Into this emulsion 

 they introduced a single, double, treble, and ten times deadly dose of 

 tetanus poison and injected these mixtures subcutaneously into mice. 

 The animals did not die. It is noteworthy that this antitoxic action of 

 tetanus poison is confined solely to the nerve tissues. It was also shown 

 that the brain and spinal cord emulsions likewise act antitoxically if they 

 are injected subcutaneously into mice and then the various lethal doses 

 afterward administered. Similarly the poisonous effect is much lessened if 

 the emulsions in question are introduced after the toxine into the body. 

 It is possible that we shall be able to isolate the poisonous group in tetanus 

 poison and find out its composition. Centrifugalized emulsions of nerve 

 tissue are perfectly inactive, which proves that we are not concerned with 

 the substances in the surrounding fluids but with the cells themselves. 

 The discovery that the antitoxine from the brain is destroyed by boiling, 

 and that the protective effect of the emulsion obtained from the spinal 

 medulla or brain is lost in the same way, is of great significance. Blumen- 

 thal 2 has at last succeeded in proving that the tetanus poison combines 

 with the brain substance, by adding the tetanus poison, which itself can 

 readily pass through a filter, to brain substance and then filtering. The 

 filtrate contains no toxine. It might be thought that perhaps the solids 

 of the nervous tissue had held it back merely mechanically. That this is 

 not the case is shown by the fact that the mixture of tetanotoxine and 

 nerve substance no longer has a toxic effect. Finally Blumenthal suc- 

 ceeded in proving that the protective action of the brain and cord grew 

 less in proportion to the amount of toxine which had been administered 

 to the animal in life. It is easy to explain why this is true. The brain 

 substance cannot, of course, combine with an infinite amount of toxine. 

 The amount taken up naturally depends upon the number of the reacting 

 groups that are present which have an affinity to tetanotoxine. If some 

 of these groups have already been satisfied, then naturally this tissue 

 will be capable of removing only a fraction of the amount which it is 

 otherwise capable of uniting with. In fact, we can determine quantita- 

 tively how much antitoxine is present in a certain amount of nerve sub- 

 stance by estimating the point at which it ceases to combine with more 

 toxine. 



We cannot here go into further details concerning the toxines and anti- 

 toxines, nor discuss the development of Ehrlich 's side-chain theory in 

 this direction any further. It is sufficient for us to have sketched the 



1 Wassermann and T. Takaki: Berliner klin. Wochenschrift, 1, 5, 1898. 

 3 F. Blumenthal: Dent. med. Wochschr. No. 12, p. 185 (1898). 



