PART I. 

 INORGANIC AGENTS. 



SECTION I. 



Water. 



Aqua, Water. Aqua Destit.lata, Distilled Water. H2O. 

 (The latter used in filling many prescriptions.) 



Action external. — The reader is referred to special articles 

 on " Cold and Heat " (p. 673 ), " Food and Feeding " (p. 648 ) 

 and " Counter Irritants" (p. 665 ), for details concerning the 

 action and uses of water, respectively, as a medium of heat 

 and cold, as an article of diet in health and disease, and as 

 a counter irritant. Cold water, externally, at first stimulates 

 reflexly heat production, with slight rise of temperature, 

 increased carbonic acid elimination and contraction of the 

 vessels and muscles of the skin. If the cold water applica- 

 tion is continued, the bodily heat falls, owing to physical 

 abstraction of heat. *' Reaction " follows the removal of 

 cold, if properly applied, with dilatation of the superficial 

 vessels (and sensation of warmth and exhilaration in man). 

 Moderate warm water (105° F.) applications stimulate cuta- 

 neous vascularity, favor diarphoresis, and diminish urinary 

 secretion. Hot water (110^-120° F.) applications act as 

 counter irritants in dilating the peripheral vessels, contract- 

 ing those in more remote parts, and relieving pain, spasm, 

 congestion and inflammation. 



Action internal. — Water is quickly absorbed and thus 

 swells the secretion of urine, and, to a less extent, that of 

 bile, saliva and pancreatic juice. Intestinal peristalsis is 

 facilitated by a considerable amount of water. Water also 

 increases tissue change, and elimination of carbonic dioxide 

 and urea ; promotes the appetite and washes out the tissues 

 and urinary tract, thus removing waste matters from the body. 



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