IN THE VICTORIAN ERA 23 



new remedy, and the serum he employed was 

 that derived from horses which had been subjected 

 to, and had recovered from, inoculations with the 

 plague bacillus. The treatment of snake bites by 

 means of curative serum will be dealt with in more 

 detail later on ; it only remains to cite it here as 

 another instance of the success which is attending 

 the new methods of protection against disease. 



Another and highly ingenious application of 

 serum has been brought forward by PfeifTer, 

 Gruber, Widal, and others. This is the so-called 

 sero-diagnosis of disease, and has been employed 

 already with success in the identification of typhoid 

 fever as such. The method sounds simple in 

 the extreme, and consists in taking a few drops 

 of blood from a patient supposed to be suffering 

 from typhoid fever and mixing them with a recent 

 cultivation in broth of genuine typhoid bacilli. 

 If the blood is derived from a typhoid-infected 

 person, then the bacilli should exhibit a curious 

 and characteristic appearance when examined 

 under the microscope. Instead of moving about 

 as individuals in various parts of the microscopic 

 field, they should be seen gathering or clumping 

 together in numerous small heaps, their move- 

 ments the while becoming paralysed. 



The State Board of Health of Massachusetts has 

 recently taken up the official sero-diagnosis of 



