INTRODUCTION. 51 



soda, forming the carbonate of lime in the teeth, bones, 

 cartilage, &c. 



Carbonate of potass a in the serum. 



Carbonate of soda in the serum, hile, saliva, tears, sweat, 

 mucus, teeth, hone, cartilage, &c. 



There are also carbonates of ammonia in the urine, and 

 of magnesia in the grease of the skin. 



3. The union of phosphoric acid with lime, soda, ammo- 

 nia, &c., as, for example, the phosphate of lime composing 

 by far the greater bulk of the bones, and also existing in 

 the teeth, cartilages, and pineal gland. 



The phosphates of soda and ammonia are seen in the 

 urine, the blood, saliva, tears, &c. 



4. The compounds of Chlorine, as those with hydrogen 

 sodium, potassium, ammonium, and calcium, forming chlo- 

 rides of these bodies, are seen in the gastric juice, blood, 

 brain, muscle, bone, cartilage, dentine, pigment, milk, 

 saliva, sweat, &c. 



5. Sulphates -of potash, soda and lime, are seen in the 

 cartilage, gastric juice, urine, bile, sweat, hair, cuticle, saliva. 

 And other binary compounds are also discovered to exist, 

 as the fluoride of calcium and alumina, in enamel of the 

 teeth, silica and oxide of manganese in the hair, oxide of 

 iron, in hematine and black pigment, oxide of titanium, 

 and sulpho-cyanide of potassium in the saliva. 



The ternary and quarternary compounds include the 

 Organic Elements, whose distinguishing feature is, that 

 they are only found in living bodies, whether animal or 

 vegetable, and that the most prominent of them possess an 

 additional element, not found in the inorganic, which is 

 nitrogen, upon whose presence depends the rapidity with 

 which some structures become putrid, or pass into decom- 

 position. This remark refers more particularly to the ani- 

 mal compounds the vegetable products, with very few 

 exceptions, are deficient in nitrogen. The Organic Elements 

 having nitrogen are, 



