SALIVARY CALCULI. 473 



Salivary Calculij Tartar, fyc. 



In man salivary calculi are of rare occurrence, but the forma- 

 tion of tartar on the teeth is continually observed : it consists 

 of earthy phosphates, epithelium-scales, a little ptyalin, and fat, 

 and when examined under the microscope there are seen 

 abundance of pavement epithelium and mucus-corpuscles with 

 fat-vesicles, and, in addition to these, numerous long acicular 

 bodies and infusoria of the genera Vibrio and Monas. 



According to Berzelius tartar is composed of earthy phos- 

 phates 79'0, salivary mucus 12*5, ptyalin TO, animal matter 

 soluble in hydrochloric acid 7' 5. 



Vauquelin and Laugier obtained similar results, namely, 

 66 parts of phosphate of lime with a little magnesia, 9 of car- 

 bonate of lime, 13 of salivary mucus, and 5 of animal matter 

 soluble in hydrochloric acid. 



Poggiale 1 analysed a salivary calculus taken from a man ; it 

 was hard, round, tuberculated, of a yellow colour, and easily 

 pulverized. It contained a large amount (94'g) of phosphate 

 of lime, with a little mucus and animal matter. 



Wurzer 2 analysed a calculus from the maxillary gland of a 

 man; it weighed three grains, was oval, of a grayish white 

 colour, and consisted principally of carbonate of lime and earthy 

 phosphates, with traces of iron and manganese. 



Salivary calculi are of frequent occurrence in the ass and 

 the horse, and are occasionally found in the dog. They consist 

 for the most part of earthy carbonates mixed with a small 

 amount of earthy phosphates and animal matters. 



The following analyses will give an idea of their composition : 



From an ass. From a horse. From a horse. 



Caventon. Lassaigne. Henry. 



Carbonate of lime . . 91-6 84 85-52 



Carbonate of magnesia . . 7'56 



Phosphate of lime . . 4'8 3 4'40 



Animal matter soluble in water . 3'6 9 2'42 



Water ... 3 



Similar concretions occur in many other parts of the organism. 

 I shall notice a few instances. 



1 Journal de Pharmacie, 1839, p. 337. 8 Archiv der Pharmacie, vol. 14, p. 254. 



