BY DR. OSCAR KATZ. 575 



The result was that the blood which was under the influence of 

 desiccation for three days at the above temperatures, was still able 

 to infect a rabbit, and cause it to perish of " chicken-cholera " 

 {about twenty-one hours after inoculation), whereas after four, 

 five, and six days from the beginning, the desiccated blood had lost 

 its virulence. 



On the other hand, the desiccated broth-culture preserved its 

 virulence so far that after two days from the beginning it was 

 still able to kill a rabbit (about twenty-seven hours after inocula- 

 tion), whereas it was not any longer efficacious when inoculated 

 after three, four, five, and six day s' desiccation. 



Series II.. 



Silk-threads saturated, December 7th, 10 a.m., with fresh liver-bipod 

 {containing large numbers of bacteria), and others saturated with fresh 

 broth-culture (having been for twenty-four hours in the thermostat at 

 40° C. — 37° C), were placed on a thin layer of sterilised sandy soil (dry) at 

 the bottom of a shallow basket made of fine brass-wire-netting. (The 

 bottom of this basket had been bent up a little where the sandy soil was put 

 on). The basket was then immediately after placed on a piece of wood, at 

 a distance of about 2| feet from the ground, in the main enclosure, at a 

 spot which was shaded off by means of a wooden post and of boards, so as 

 to leave the spot only at the south side free and accessible. The basket 

 was sheltered from rain by putting coverings over the top of the boards 

 mentioned. 



The virulence of the original material (blood and broth -culture) was 

 tested by inoculating rabbits, one with silk-thread charged with blood, and 

 the other with silk-thread containing broth-culture. Both rabbits died of 

 •' chicken-cholera," 10 and 21 hours, respectively, after inoculation. 



The effect of the drying-up of the silk-threads was ascertained by 

 inoculating rabbits after 4, 8, 12, 24, 48, 72, 96, 120 hours from the 

 beginning. Within this period, from December 7th, 10.15 a.m., to 

 December 12th, 10.15 a.m., the thermometer in the shaded place regis- 

 tered temperatures of between 20|? C. (lowest) and 29|° C. (highest). 



