OXYGEN HYDROGEX. 43 



FIRST DIVISION. 



The gaseous or liquid immediate principles, and those which are not 



saline. 



1. Oxygen. (0.) 



Oxygen is to be regarded as an immediate principle only when 

 existing in a free state in the body, as in venous and arterial blood, 

 in the air-cells and bronchial tubes, and sometimes in the stomach. 



The whole amount of free oxygen in the body averages about 

 77 J grains, and in ( the blood alone 61 grains* There are about 9f 

 cubic inches of oxygen in the arterial blood, and 14JJ inches in the 

 venous. But the proportional amount is greater in the former than 

 in the latter, in the ratio of 2.41 to 1, and sometimes even of 3 to 

 1.17 ; since there is but two-thirds as much blood in the arterial 

 system as in the venous. (Robin and VerdeiL) 



Oxygen exists in the blood in a liquid state (in a state of solution), 

 and probably mostly in the corpuscles alone. 



The amount of oxygen received into the lungs of an inhabitant 

 of Potosi, 13,000 feet above the level of the sea, however, equals 

 only two-thirds of that consumed by an inhabitant of a maritime 

 city. 



The theory of Liebig, adopted by French and German chemists 

 generally, that in the case of the higher animals the oxygen consumed 

 in respiration is destined to combine finally with the tissues and the 

 calorific (respiratory) elements of the food (starch, sugar, fats, &c.), 

 thus forming carbonic acid, water, &c.,/or the purpose of producing 

 and maintaining the animal heat, is evidently too narrow a view of 

 this subject. Heat is the result of nutritive changes of all kinds, 

 but not the direct object of them. It is in its action on the tissues 

 of the body, as a vital stimulus, that the prime importance of oxy- 

 gen consists; though the incidental development of heat, as above 

 stated, is indispensable to the organism. 



The quantity of oxygen consumed in a year by an adult male is 

 about 800 pounds. 



2. Hydrogen. (H.) 



Free hydrogen exists normally in the stomach, colon, and cascum, 

 forming, of all the contained gases, 3.55 per cent, in the first organ, 

 from 5.4 to 11.6 per cent, in the colon, and 7.5 in the cascum. This 



