208 UNORGANISED FLUIDS. 



inferred from a knowledge of their structureless character. 

 In the treatise on Crystallography, however, many interest- 

 ing and important details will be given. 



The UNORGANISED FLUIDS comprise the saliva, the bile, 

 the sweat, the urine, and the gastric, pancreatic, and lacrymal 

 fluids ; these several fluids especially deserve the name of 

 secretions, since they are elaborated by large and complexly 

 organised glands. 



THE SALIVA. 



The saliva is a peculiar fluid secreted by the parotid, sub- 

 maxillary and sublingual glands, from which it is conveyed 

 by certain ducts into the mouth, where it becomes mingled 

 with the buccal mucus. The amount of saliva secreted 

 during the day is estimated at from ten to twelve ounces; 

 during salivation either spontaneous, or induced by mercury, 

 the quantity may exceed two or three quarts. It is worthy 

 of remark, however, that in these latter cases the mercury has 

 never been detected in the saliva. 



Mitscherlich * made the following observations on a person 

 having a salivary fistula, and in whom the saliva could be 

 collected directly as it flowed from Steno's duct. He found 

 that there was no flow of saliva while the muscles of mastica- 

 tion and of the tongue were in complete repose, and all ner- 

 vous excitement avoided. He observed also, that during the 

 acts of eating and drinking, especially at the commencement, 

 the secretion was most abundant, and in proportion to the 

 stimulating nature of the food and the degree to which it 

 was masticated. From two to three ounces of saliva flowed 

 from the duct in the course of twenty-four hours. 



The solid constituents of the saliva are composed of fat, 

 ptyalin, watery and spirituous extractive matters, a little 

 albumen, certain salts, a trace of sulphocyanogen, mucous 

 corpuscles, epithelial scales, and lastly, corpuscles resembling 

 mucous globules, which have been termed salivary corpuscles, 



* Rust's Magaz., vol. xl. 



