BY DR. OSCAR KATZ. 577 



The result was this : — 



The blood thus exposed to desiccation preserved its virulence 

 when inoculated after four, eight, and twelve hours ; when inocu- 

 lated after twenty-four hours and more from the beginning, it had 

 est its efficacy on rabbits. 



The desiccated broth-culture proved virulent only when inocu- 

 lated four hours after the beginning of the experiment. The 

 rabbit succumbed to " chicken-cholera " twenty-six hours after 

 inoculation. Subsequent inoculations, eight, twelve, and more 

 hours after the beginning, were attended with negative results. 



Series III. 



Silk-threads saturated, December 7th, 10 a.m., with virulent material 

 ( blood and broth-culture) derived from the same sources as the material 

 used in Series II., were placed on sterilised dry sandy soil, which in a thin 

 layer covered the bottom of a small shallow wire-gauze basket, similar to 

 that in Series II. 



Annotation : Control of virulence as in Series II. 

 At 10.10 a.m., same day, this basket was placed on some available spot 

 on the Island ; this spot was accessible to the sun's rays all day long. The 

 bottom of the wire-basket was placed flat on the perfectly dry sandy 

 surface of that spot. This latter was also accessible to the wind or breeze 

 prevailing during the experiment. 



The silk-threads remained there from 10.10 a.m. to 6.1.0 p.m., i.e., for 

 eight hours. Within this period rabbits were inoculated 1, 2, 4, 6, and 8 

 hours from the time the silk-threads were exposed. 



A thermometer was laid on the soil near where the basket with the silk- 

 threads stood. Details about the temperatures at the surface of the soil, 

 during the course of the experiment, are given in the accompanying table. 



December 7th: — 



10.15 a.m., 45^ C; 10.45 a.m., 50° C— Sunshine for about ten 



minutes. 

 11.15 a.m., 47° C. — Sunshine for about ten minutes since last 



observation. 

 11.45 a.m., 42|*^ C. — Few minutes sunshine. 



12 noon, 35° C. —Cloudy for about twelve of last fifteen minutes. 

 37 



