362 Veterinary Medicine. 



vesicles of three children who were suffering from the disease^ 

 and from animals attacked in two successive epizootics. Withr 

 this'they first successfully inoculated a calf and from the pure 

 cultures obtained from its blood, inoculated three calves and a 

 young pig. 



lyOfHer and Frosch, the recent commission on foot and mouth 

 disease in Germany, report that no organisms could be seen nor 

 cultivated from the lymph found in recent bullae of the buccal 

 mucosa, though this lymph later passing through a Berkefield 

 filter still proved virulent when inoculated on calves. A Pasteur 

 filter arrests it. 



They found that the lymph became inert when dried for 24 

 hours at 31° C. (88° F.), while it retained its vitality and viru- 

 lence after exposure for 9 months to a temperature of 0° C. They 

 concluded that it could not penetrate through the unbroken skin 

 nor mucosa, and that it was most effective when injected into the 

 blood or peritoneal cavity. One attack conferred immunity for 5 

 months. Blood from immune animals, injected into susceptible 

 ones does not confer immunity, but 75 per cent, could be ren- 

 dered immune if injected with a mixture of the lymph from the 

 vesicle and double the same amount of the blood from the immune- 

 animal. Animals so treated become immune to 100 times the 

 infecting dose. Filtered lymph was still virulent and the com- 

 mission suggests that the microbe may be so small as to pass- 

 through the filters and escape discovery by the most powerful 

 lenses. An object one-fifth the size of the smallest known bacil- 

 lus — that of influenza — would be invisible under our best micro- 

 scope. 



By actual experiment the virus has been found in the nose, 

 larynx, bronchia, .stomach and intestines, but into all these the- 

 virulent lymph of the bullae can find its way. In the intestines, 

 indeed, in cases caused by feeding, bullae have been found on the 

 mucosa. 



A most important question would be that of the virulence of the 

 milk, but inasmuch as the vesicles appear on the teats and even 

 on the openings of the milk ducts, and in bursting discharge their 

 contents with the milk into the pail, the milk becomes per force 

 infecting. The experience of Hertwig and his students who- 

 infected themselves by drinking the warm milk by way of experi- 



