Group 1. _Mineral Substances_.
Examples: Water; Common Salt; Ashes of Plants and Animals.
Group 2. _Non-nitrogenous force-producing Substances_, _incapable of
forming Flesh or Muscle_.
Examples: Sago, Arrowroot (_Amylaceous_); Sugar, Figs, Dates
(_Saccharine_); Animal and Vegetable Fats and Oils (_Oleaginous_).
Group 3. _Nitrogenous Substances capable of producing both Flesh and
Muscle_.
Examples: Eggs (_Albuminous_); Wheat, Flesh (_Fibrinous_); Peas, Cheese
(_Caseinous_).