CANCER BIOPLASTS. 153 



outside, where they grow and multiply. By their 

 accumulation, the pressure upon the vessel becomes 

 greater, and at last its calibre will be completely 

 obliterated. From such tubercle collections minute 

 bioplasts may be readily detached, and after having 

 found their way into a pervious lymphatic vessel, or 

 blood capillary, might be carried to distant parts and 

 grow there. In this way tubercles are developed in 

 many different parts of the body and in the substance 

 of many different tissues and organs. If a particle 

 of fluid, holding living tubercle-germs in suspension, 

 were introduced by inoculation into a weakly or- 

 ganism, the disease might be produced. 



Cancer Germs. Whilst it is almost certain cancer 

 could be introduced by direct inoculation into the 

 organism of a healthy person, many circumstances 

 render it in the highest degree improbable that living- 

 germs detached from the growth, could, under any 

 circumstances, gain access to another organism 

 through the air breathed, or in any other manner pass 

 into the blood or tissues, as long as the surface 

 remained uninjured. Cancer germs would probably 

 live for some time in animal fluids out of the body, and 

 it is by no means impossible that we may succeed in 

 growing them in glass vessels away from their natural 

 seat of growth, and watch the changes which occur 

 under our microscopes ; but it is exceedingly doubtful 

 if these germs would long retain their vitality if 

 removed from the fluid which nourished them. Some 



