Tubercles of Babes 469 



Hogyes, of Budapest,* believes that Pasteur was mis- 

 taken in supposing that the drying was of importance in 

 attenuating the virus, and thinks that dilution is the chief 

 factor. He makes an emulsion of rabbit's medulla (i gram 

 of medulla to 10 c.c. of sterile broth) as a stock solution, to 

 be prepared freshly every day, and uses it for treatment, 

 the first dilution used being i : 10,000; then on succeeding 

 days i : 8000, i : 6000, i : 5000, i : 2000, i : 1000, i : 500, 

 i : 250, i : 200, i : 100, and finally the full strength, i : 10. 



Cabot f prepared a stock solution of 8 parts of rabbit's 

 brain and 80 parts of glycerin and water. The quantity 

 of glycerin added comprised one-fifth of the total bulk. 

 After the emulsion was made it was filtered through sterile 

 cheese-cloth. This emulsion containing the glycerin, if 

 kept in the ice-chest, will be of standard virulence during 

 the entire period of immunization. As the result of his 

 experiments, Cabot found the dilution method attended 

 with danger to the animal immunized, which is not true of 

 the dried-cord method of Pasteur. The latter method is 

 therefore the one to be preferred. 



Though the essential cause of rabies has not yet been dis- 

 covered, its lesions can be found in the medulla oblongata 

 and in the spinal ganglia. These consist in certain cellular ag- 

 gregations known as the "tubercles of Babes," and in certain 

 degenerative changes in the ganglionic nerve-cells. The regu- 

 larity with which these changes were observed by Babes led 

 him to regard them as useful for diagnosticating the disease, 

 and Van Gehuchten and Nelis, and Ravenel and McCarthy 

 have confirmed this opinion. Ravenel and McCarthy { think 

 that Babes gives undue prominence to the rabic tubercle, 

 which consists of an aggregation of embryonal cells about the 

 central canal of the cord, about the ganglionic nerve-cells, 

 and about the capillary blood-vessels, but that the lesions of 

 the nerve-cells are pathognomonic if taken in connection with 

 the clinical manifestations of the disease. These ganglion-cell 

 changes consist in degeneration and chromatolysis. There 

 is loss of the prolongation and a progressive modification, 

 and even total disappearance of the nuclei, a dilatation of 



*Acad. des Sciences de Buda-Pest, Oct. 17, 1897; "Centralbl. f. 

 Bakt. u. Parasitenk.," 1887, n, 579. 



t "Journal of Experimental Medicine," 1899, vol. iv, No. 2. 



J " Trans. Phila. Pathological Society," N. S., vol. m, 1900, p. 

 231 ; and " University Medical Magazine," Jan., 1901. 



