43. These elements are divided into _metallic_ and _non-metallic_ substances. The metallic substances are _Po-tas´si-um_, _So´di-um_, _Cal´ci-um_, _Mag-ne´si-um_, _A-lu´min-um_, _I´ron_, _Man´ga-nese_, and _Cop´per_. The non-metallic substances are _Ox´y-gen_, _Hy´dro-gen_, _Car´bon_, _Ni´tro-gen_, _Si-li´-ci-um_, _Phos´phor-us_, _Sul´phur_, _Chlo´rine_, and a few others. 44. POTASH (potassium united with oxygen) is found in the blood, bile, perspiration, milk, &c. 45. SODA (sodium combined with oxygen) exists in the muscles, and in the same fluids in which potash is found. 46. LIME (calcium combined with oxygen) forms the principal ingredient of the bones. The lime in them is combined with phosphoric and carbonic acid. 47. MAGNESIA (magnesium combined with oxygen) exists in the bones, brain, and in some of the animal fluids; as milk. 48. SILEX (silicium combined with oxygen) is contained in the hair and in some of the secretions. 49. IRON forms the coloring principle of the red globules of the blood, and is found in every part of the system. _Observation._ As metallic or mineral substances enter into the ultimate elements of the body, the assertion that all minerals are poisonous, however small the quantity, is untrue. -=-=-=-=-=-=-=-=-=-=-=-= 42. What is an ultimate element? Give examples. 43. How are they divided? Name the metallic substances. Name the non-metallic substances. 44. What is said of potash? 45. Of soda? 46. Of lime? 47. Of magnesia? 48. Of silex? 49. What forms the coloring principle of the blood? What is said of mineral substances? -=-=-=-=-=-=-=-=-=-=-=-= 50. OXYGEN is contained in all the fluids and solids of the body. It is almost entirely derived from the inspired air and water. It is expelled in the form of carbonic acid and water from the lungs and skin. It is likewise removed in the other secretions. 51. HYDROGEN is found in all the fluids and in all the solids of the body. It is derived from the food, as well as from water and other drinks. It exists in the greatest abundance in the impure, dark-colored blood of the system. It is removed by the agency of the kidneys, skin, lungs, and other excretory organs. 52. CARBON is an element in the oil, fat, albumen, fibrin, gelatin, bile, and mucus. This element likewise exists in the impure blood in the form of carbonic acid gas. Carbon is obtained from the food, and discharged from the system by the secretions and respiration. 53. NITROGEN is contained in most animal matter, but is most abundant in fibrin. It is not contained in fat and a few other substances. _Observation._ The peculiar smell of animal matter when burning is owing to nitrogen. This element combined with hydrogen forms _am-mo´ni-a_, (hartshorn,) when animal matter is in a state of putrefaction.