([1]) If the elements were only capable of combining with each other in simple ratios, the number of their combinations would be as limited as that of the letters of the alphabet; but as one, two, or more atoms of oxygen can combine with one, two, or more atoms of other elements, we can assign no limits to the number of possible combinations. There are hundreds of distinct substances formed of but two elements, namely, hydrogen and carbon.
([2]) In a paper by Professor Sullivan, of Dublin, the conversion of one of these substances into another outside the animal mechanism, is almost incontrovertibly proved.
([3]) Experimental Inquiry into the Composition of some of the Animals Fed and Slaughtered as Human Food. By John Bennet Lawes, F.R.S., F.C.S., and Joseph Henry Gilbert, Ph.D., F.C.S. Philosophical Transactions of the Royal Society. Part II., 1860.
([4]) From the Greek plasso, "to form." Plastic materials are sometimes termed formative elements; both terms imply the belief that they are capable of giving shape, or form, not only to themselves, but also to other kinds of matter not possessed of formative power.