1835.] Human Saliva. 381 



to be conducted under the receiver of an air pump. The 

 quantity of the fixed constituents of the saliva, varies 

 slightly in different trials, but is in proportion to the 

 specific gravity. 



Saliva of sp. gr. 1*0072 contains 1*468 per cent, of fixed 

 matter. 1*0079 „ 1*551 



1*0083 „ 1*632 



66547 grms. (1024*7 grs.) of filtered saliva of sp. gr. 

 1*0079 being neutralized with dilute sulphuric acid, yielded 

 a flocky white precipitate, which when collected and 

 washed on the filter, weighed 0*061 grms. (*93 grs.) The 

 liquid which passed through the filter was evaporated 

 under the receiver of an air pump, and left a residue 

 amounting to 1*051 grm. (16*17 grs.) 0*543 grm. (8*3 grs.) 

 of this matter dissolved in alcohol of sp. gr. 0*863, and the 

 other results after treatment with water and alcohol were, 



grm. grs. 



Insoluble in water and alcohol 0*212 3*264 



Soluble in water, insoluble in alcohol ... 0*357 5*497 

 Soluble in water, insoluble in absolute alcohol 0*190 2*926 

 Soluble in water and absolute alcohol . . . 0*340 5*236 



1*099 16*923 

 66*775 grms. (1028J grs.) of saliva of sp. gr. 1*0083 were 

 without being neutralized, evaporated to dryness by the 

 air pump and yielded 1*08 grm. (16*6 grs.) 



These were analyzed and gave, grms. grs. 



Insoluble in water and alcohol (sp. gr. 0*863) 0*281 4*327 

 Soluble in water and insoluble in alcohol 



(sp. gr. 0*863.) 0*352 5*420 



Soluble in water and insoluble in alcohol 



(sp. gr. 0*800.) 0*296 4*558 



Soluble in water and alcohol (sp. gr. 800.) 0*192 2*956 



1*121 17*261 

 The portion which is not dissolved either by water or 



alcohol is salivary mucus. Acetic acid swells it up, but 



does not dissolve any of it either in the cold or by boiling. 



Sulphuric acid gives it a red tinge, but causes no other 



change. 



Hydro-chloric acid, without heat after a long time, but 



speedily by boiling, produces a blue solution. 



