NATURE OF CYTOST 231 



was unwholesome, owing to the dust raised which al- 

 ways produced feverish headaches after a few hours 

 of it." And (page 94) "The efifect of being surrounded 

 with so much organic dust from the mummies was to 

 give me a bad infection of the breathing passages." 



Now it may be recalled that we have found that 

 the endodermal cells of the lung are peculiarly sensi- 

 tive to cytost and that various respiratory disturbances 

 varying from sneezing to a true pneumonia could be 

 induced by the introduction of minute quantities of 

 cytost into the respiratory tract of animals. This re- 

 sult was accomplished by the simple expedient of 

 spraying the cages of animals with a potent extract 

 of autolyzed tissue as well as by coating the paws of 

 cats with a paste containing cytost. 



It would seem that the discomfort experienced by 

 Petrie and his associates when in contact with the 

 mummy dust was essentially the same as that experi- 

 enced by the cats whose cages had been sprayed with 

 cytost. One may raise the argument that exposure 

 to any atmosphere containing finely particulate mat- 

 ter will cause some respiratory distress. This of course 

 is true, but in general unless the dust contains some 

 toxic substance its effects are purely mechanical and 

 pass away very shortly after the exposure. 



Such, however, is not the case with cytost, for, as 

 our experiments have shown, cytost-laden air induces 

 pathological conditions which last for some time. In 

 this connection, it is of interest to note that Petrie com- 

 plains that the mummy dust caused headaches and 

 "colds" which prevented further work for a few days, 

 and this is what we should expect from exposure to 

 cytost, but not from exposure to a dry, non-toxic dust. 



