Parasites of Muscular and Connective Tissue. 433 



ond piece weighing eight pounds was only sterilized in the centre 

 at the end of four hours of continuous boiling. The best rough 

 test is whether the interior of the cooked piece of meat has had 

 its center completely coagulated and rendered of a pale brownish 

 color. If not, and if the red blood still oozes from its cut surface 

 the temperature has been insufficient to kill trichinae. Again 

 pork that is hurriedly roasted will usually show the red blood 

 oozing from the centre when cut, and the heat has not risen to 

 the killing point Qi4o^F.). The time of exposure, the intensity 

 of the heat, and the suddenness of the cooling all affect the re- 

 sult. The roast that is kept in a warm atmosphere for some time 

 after removal from the fire continues to transmit the heat of its 

 outer layers to the interior, which manifestly cannot happen 

 when it is suddenly chilled. Sausages are especially dangerous 

 as many eat them after a slight frizzling of the surface, which in 

 no sense affects the interior. 



Other conditions affect the trichinae, reducing their vitality and 

 rendering them more susceptible to the action of heat. Three 

 days exposure to the open air at — 20° to — 25° C. ( — 3° to — 13° F. ) 

 failed to kill trichinae (Leuckart), yet Fiedler says they die when 

 actually exposed to — 14° C. (+ 7" F. ) and Kiihn found that 

 they had perished after two months in an ice-house, though at a 

 higher temperature. 



In this connection it is interesting to note that the trichinae sur- 

 vive one hundred days in putrefying meat, showing that mere 

 lapse of time is unimportant. 



The thorough salting of the pork slowly kills the trichinae. A 

 light salting is ineffective, but the thorough penetration of the 

 salt in quantity to all parts of the ham or bacon, destroys the 

 trichinae in the course of a month, or two months in the case of 

 the largest hams. Thus it is that in spite of all the complaint in 

 Germany of the trichinae in America, a standing reward has been 

 offered for years past for a single case of trichinosis that can be 

 indubitably traced to the eating of American ham or bacon, yet no 

 case of the kind has been adduced. Many outbreaks of trichino- 

 sis have been recorded in Germany during this period but all have 

 been traced to the consumption of home-grown pork. Direct ex- 

 periments on small animals with salted American pork have been 

 made at Paris, Lyons, Rouen, Thionville, Strassburg, Munich, 

 28 



