MINERAL CONSTITUENTS OF THE CELLS. 23 



In the ordinary method of determining the mineral bodies in cells, 

 fluids and tissues, namely by incineration, no positive knowledge can 

 be acquired as to the division of the mineral bodies or their form of 

 combination. On incineration we obtain not only a mixture of the min- 

 eral bodies of the nucleus and protoplasm, but, as is true for all animal 

 fluids and tissues, the original relationship is markedly changed. The 

 combinations between the colloidal and mineral substances are destroyed, 

 carbon dioxide discharged, and sulphuric acid and phosphoric acid 

 may be produced from the organic bodies. The ordinary chemical 

 analysis is not sufficient for the study of the mineral constituents of the 

 fluids or tissues, their forms of combination and action; hence we must 

 resort to physical-chemical methods. 



As a result of the investigations carried on by these methods, the 

 conclusion has been reached, irrespective of the importance of the min- 

 eral bodies for the osmotic tension in the cells and tissues, that the 

 part taken by the mineral bodies in cell life is essentially dependent 

 upon the action of the ions. The investigations of MAILLARD on the 

 toxic action of copper salts, and of PAUL and KRONIG l On that of mer- 

 cury salts, acids, and alkalies, offer examples. From these investiga- 

 tions it follows that the toxicity is dependent upon the dissociation, 

 and that it is not dependent upon the total amount of, for example, 

 copper or mercury salts present in the solution, but rather upon the 

 number of copper or mercury ions. 



Important and conclusive investigations, which are considered as 

 beautiful and instructive examples of the importance of ions for cell 

 life, have been carried out by LOEB and his collaborators. Some of these 

 examples will be discussed in the next chapter (II). 



The chief mass of the cells consists of colloids, and as the normal func- 

 tion of the cells is connected with a certain physical condition of the 

 protoplasm, it is natural to consider the action of ions in relationship 

 to the changes in the condition of the colloids. These colloids can be 

 precipitated by electrolytes, and it seems as if we are here dealing with 

 ion action. A physiologically balanced salt mixture suitable for the 

 normal functions may also be produced by the antagonism of the ion 

 action in a complex solution containing several salts (LOEB). Changes 

 in one or the other direction must correspondingly also bring about 

 changes in the state of the colloid by the action of the ions. The action 

 of ions in these cases, as well as the nature of colloids and the reasons 

 for the change in their conditions, is a very difficult question, and this 

 will be discussed in the following chapter (II). 



1 Maillard, Journ. de Physiol. et Path., 1; Paul and Kronig, Zeitschr. f. physikal. 

 Chem., 12, and Zeitschr. f. Hygiene, 25. 



