DIGESTION. 



173 



HAMMERBACHER found in 1000 parts of the ash from human saliva 

 (potash 457.2, soda 95 9, iron oxide 50.11, magnesia 1.55, sulphuric anhydride 

 SO 3 ) 63.8, phosphoric anhydride (P a O B ) 188.48, and chlorine 183.52. 



correspond fairly well with those representing the average secre- 

 tion from 1 grin, of gland in animals, namely, 14.2 grms. in the 

 horse and 8 grms. in oxen. The quantity of secretion per hour 

 may be 8 to 14 times greater than the entire mass of glands, and 

 there is probably no gland in the entire body, as far as we know at 

 present the kidneys not excepted whose ability of secretion under 

 physiological conditions equals that of the salivary glands. A re- 

 markably abundant secretion of saliva is induced by pilocarpin, 

 while atropin, on the contrary, prevents it. 



Though an abundant secretion of saliva is produced, as a rule, 

 by an increased supply of blood, still it is not a simple nitration 

 process, as seen from the following circumstances. The secretion- 

 pressure is greater than the blood -pressure m the carotid, and in 

 poisoning by atropin, which paralyzes the secretory nerves, an in- 

 creased supply of blood is produced by irritation of the chorda, but 

 no secretion (HEIDENHAIN). The salivary glands have moreover 

 a specific property of eliminating certain substances, such as potas- 

 sium salts (SALKOWSKI), iodine and bromine combinations, but not 

 others, such as iron combinations. It is also noticeable that the 

 saliva is richer in solids when it is eliminated quickly by gradually- 

 increased irritation, and in larger quantities than when the secre 



