SALIVA. 389 



1. The saliva of the horse was examined by Lassaigne in 1821.* 

 It was colourless, had a slight smell, and on exposure to the air 

 become muddy, and let fall a white precipitate consisting of car- 

 bonate of lime mixed with a little phosphate. It was slightly al- 

 kaline, and when heated, let fall some flocks of albumen. Being 

 evaporated to dryness, it left 3| per cent, of matter consisting of 



1. Animal matter soluble in alcohol. 



2. Animal mater soluble in water. 



3. Albumen. 



4. Trace of mucus. 



5. Chlorides of potassium and sodium. 



6. Soda. 



7. Carbonate of lime. 



8. Phosphate of lime. 



2. The saliva of the dog was pale yellow, mucilaginous, and 

 slightly muddy ; when evaporated, it left 2-58 per cent, of resi- 

 due. From this residue alcohol extracted common salt, with a 

 very little lactate of soda, and a mere trace of extract of meat. 

 The portion insoluble in alcohol consisted chiefly of salivin unit- 

 ed to soda. It possessed exactly the characters of salivin from 

 human saliva, 



3. The saliva of the sheep was very liquid, and not mucilagi- 

 nous. Its taste was feebly saline, and its reaction was alkaline. 

 It left a residue, when evaporated to dryness, amounting to 1-68 

 per cent, of the saliva. This residue was a thick white membrane 

 which attracted some moisture when exposed to the air. Alco- 

 hol extracted from it common salt, and was reddened by per- 

 chloride of iron, indicating the presence of sulphocyanic acid. 

 The residue left by the alcohol yielded to water a mere trace of sa- 

 livin, but several saline substances. The insoluble residue was 

 brittle and membranous. It did not dissolve nor gelatinize in 

 acetic acid. 100 parts of this saliva contained, 



1. Water, . . . 98-90 



2. Masters soluble in alcohol, viz. much extract of meat, a 

 substance which caused common salt to crystallize in oc- 

 tahedrons, common salt, and a little sulphocyanate of 

 soda, . . . O'll 



3. Matters soluble only in water, viz. traces of salivin, 

 much phosphate of soda, much chloride of potassium and 

 carbonate of soda, . . 0'82 



* Ann. de Chim. et de Phys. xix. 176. 



