380 Chemical Properties of Animal Fluids. [Nov. 



Water 092-9 



A peculiar animal matter 2*9 



Mucus 1-4 



Alkaline muriates 1 - 7 



Lactate of soda and animal matter . • 09 



Pure soda 0-9 



1000-0 



Two of these ingredients require further notice. 

 The peculiar animal matter of the saliva is obtained by adding 

 spirit of wine to dried saliva, which dissolves the muriates, lac- 

 tates, &c. The soda which remains in the insoluble portion is 

 then extracted by fresh spirits slightly acidulated with acetous 

 acid. The residue is mucus mixed with the peculiar salivary 

 matter, which last may be dissolved by water, leaving behind 

 the insoluble mucus. 



This peculiar matter is therefore soluble in water, but not in 

 spirits of wine. The solution in water, when evaporated to 

 dryness, leave; a transparent mass that easily again dissolves in 

 cold water. This solution is not precipitated either by alkalies, 

 or acids, or subacetate of lead, or muriate of mercury, or tannin; 

 neither does it become turbid by boiling. 



The mucus of the saliva is readily procured by mixing saliva 

 with distilled water, from which the mucus gradually subsides, 

 and it may then be collected on the filter and washed. In this 

 state it is white, and would seem to contain phosphate of lime 

 mixed with it. This mucus is quite insoluble in water; it be- 

 comes transparent and horny in the acetic, sulphuric, and mu- 

 riatic acids, but does not dissolve in them, and the alkalies 

 separate nothing from them. The mucus therefore contains no 

 earthy phosphate, though its appearance would lead to suspect 

 this earthy salt. It dissolves in caustic alkali, and is again sepa- 

 rated from it by the acids. A small proportion escapes the action 

 of the alkali, but yields to muriatic acid, and is not separable 

 from this acid by an excess of alkali. The mucus of the saliva 

 is very easily incinerated, and though no phosphate of lime is 

 detected in it by the acids in its natural state, a considerable 

 portion of phosphate appears in the ash after combustion. 



Is this mucus secreted in the salivary glands, or is it only the 

 common mucus of the mouth ? The latter appears most pro- 

 bable, though I confess that the large quantity of this mucus 

 contained in the saliva, and the great difference between its 

 chemical properties and those of the nasal mucus, throw some 

 doubt on this opinion. 



It is this mucus that produces the tartar of the teeth, v hich 

 at first is only mucus precipitated on the surface of the teeth and 



