236 METAMORPHOSIS OF TISSUE. 



not be contained in the blood either in a free or loosely combined 

 form. We can only assume this much, that the process of oxida- 

 tion in the blood does not possess any high degree of intensity, 

 and that the manner in which the process is here accomplished is 

 more involved than we should at first sight be disposed to 

 believe. 



Although we may not overrate the importance of the alkali in 

 connection with the process of oxidation in the blood, the above 

 experiments might probably lead us to the erroneous conclusion 

 that no oxidation can take place within the organism, indepen- 

 dently of alkalies. We call such a view erroneous, for independently 

 of the circumstance, that it cannot be denied that a certain oxida- 

 tion takes place in many acid fluids as well as in the substance of 

 the organs, there are many points which indicate that other con- 

 ditions may probably contribute to increase the oxidising capacity 

 existing in the blood. Many of the salts of the organic acids, as for 

 instance, the alkaline lactates, tartrates, and citrates, do not become 

 so rapidly oxidised in the air, even when an excess of alkali is pre- 

 sent, as the gallates or pyrogallates ; for if solutions of these salts be 

 injected into the blood, they not only become much more rapidly 

 oxidised than would be the case externally to the animal body in 

 the atmosphere, but almost more quickly than if the salts were di- 

 rectly incinerated (see vol. i. p. 97). Other substances again, such 

 as salicin, theme, &c., are very rapidly oxidised in the blood, 

 whilst they continue for a long time to resist the action of alkalies 

 or oxygen, when exposed to their influence at a temperature of 

 37 externally to the living organism. The rapidity and readiness 

 with which so many substances are oxidised or changed in the 

 blood cannot be solely referred to the simultaneous presence of a 

 mass of bodies undergoing various metamorphoses, to any peculiar 

 condensation in which the oxygen occurs in the blood, or to any 

 similar relations which control the effects of the alkalies ; but 

 they must rather be referred to conditions which we are still unable 

 to deduce from any definite physical or chemical processes, owing 

 to the extremely complicated nature of the chemical changes going 

 on in the blood. We will here only refer, by way of illustration, 

 to that condition of oxygen in which it exhibits, as ozone, a far 

 more energetic force of affinity. 



However much we may differ from some of Schonbein's modes 

 of explanation and the conclusions he deduces from his discoveries, 

 the majority of the results which he obtains are indubitable facts, 

 whilst it is almost a necessarv deduction from his most recent 



