1 6 GENERAL HISTOLOGY. 



5. The chemistry of bioplasm is a difficult if not impossible 

 study, since life departs before analysis. There is also in 

 every tissue a mixture of elementary, formative and retrogres- 

 sive materials which cannot be separated. 



6. As all bioplasm appears alike, although its development 

 and transformation produce materials which differ in physical 

 properties and chemical composition, it is probable that the 

 elements do not combine as in inorganic matter, the ordinary 

 chemical affinities being suspended or modified by the pres- 

 ence of the vitalizing power. Bioplasm, for example, is semi- 



'fluid, yet it will not freeze like water, at 32 F. It is doubtful 

 if it will really freeze until life departs. 



7. Bioplasm (when not dormant) is in a state of active 

 molecular change, or unstable equilibrium, since it is constantly 

 appropriating pabulum and transforming itself into formed 

 material or tissues. It is doubtful if ordinary chemical com- 

 bination occurs, the activities being too transitory for real 

 combination. The elementary atoms or molecules constantly 

 pass through the phase of bioplasm, to be rearranged in the 

 composition of organic products. 



8. When bioplasm is changed into formed or retrogressive 

 material, more permanent combination of chemical elements 

 occurs. Free oxygen may be absorbed and complex com- 

 pounds result, often baffling analysis. If the life of the bioplast 

 is suddenly destroyed, the result is water, albumen and fat- 

 Sometimes fibrin is also formed, which differs from albumen 

 by its spontaneous coagulation, while albumen requires heat, 

 nitric acid, etc., to coagulate it. Certain salts, as sodium chlo- 

 ride, etc., may also result from the sudden death of bioplasm. 

 Fatty matter increases for some time after death. In slower 

 transformations, equivalent to slow molecular death, different 

 materials result, depending on various circumstances, espe- 

 cially the quantity of oxygen present. These materials are fat, 

 sugar, amyloid matter, biliary acids, milk, etc. 



9. Many important changes may occur in formed material 

 after production. It may undergo condensation, during which 

 structural peculiarities maybe manifested. It may dry gradu- 

 ally, and remain long unchanged, or if fluid may split into sol- 



