384> THE LAWS OF ORGANIC 



the blood, in harmony with such changes, does 

 not exhibit the same character, and, in many in- 

 stances, will not even coagulate* The condi- 

 tions which produce the inflammatory coat in 

 disease, are the same as those that predominate 

 in childhood simply modified. When they ex- 

 ist in disease, we have increase of temperature, 

 augmented action of the heart and arterial sys- 

 tem, a vascular or florid appearance of the sur- 

 face of the body ; and when they occur at an 

 early period of life, we have similar symptoms, 

 differing only in degree. The frequent respira- 

 tions, supposing other conditions of the system 

 favourable, as they are almost universally in 

 childhood, must be allowed to deteriorate, in a 

 given time, a greater quantity of air than when 

 these are slow or imperfect. The air which is 

 inspired contains a vivifying principle, viz. oxy- 

 gen ; and if a greater quantity of air be breath- 

 ed in a limited period, a greater quantity of oxy- 

 gen must be received by the blood in the lungs 

 in the same time ; and it is to this agent we 

 must refer the oxygenated or arterialized pro- 

 perties of the sanguineous fluid. 



CCCCLVIII. In the child the arterial blood 

 is more florid than the same in advanced 

 life, or at least the venous is not so dark as at 

 this period. When the body is subjected to 

 great heat or exercise, the venous loses its ordi- 



