Much, in fact, depends on definition here; and, in reference to modification, it may be regarded as arbitrary when identity shall be admitted to cease and difference to begin. There are the old Greek puzzles of the Bald Head and the Heap, for example. How many grains, or how many hairs, may we remove before a heap of wheat is no heap, or a head of hair bald? These concern quantity alone; but, in other cases, bone, muscle, brain, fungus, tree, man, there is not only a quantitative, but a qualitative difference; and in regard to such differences, the word modification can be regarded as but a cloak, under which identity is to be shuffled into difference, but remain identity all the same. The brick is but modified clay, Mr. Huxley intimates, bake it and paint it as you may; but is the difference introduced by the baking and painting to be ignored? Is what Mr. Huxley calls the “artifice” not to be taken into account, leave alone the “potter?” The strong firm rope is about as exact an example of modification proper—modification of the weak loose hemp—as can well be found; but are we to exclude from our consideration the whole element of difference due to the hand and brain of man? Not far from Burn’s Monument, on the Calton Hill of Edinburgh, there lies a mass of stones which is potentially a church, the former Trinity College Church. Were this church again realized, would it be fair to call it a mere modification of the previous stones? Look now to the egg and the full-feathered fowl. Chaucer describes to us the cock, “hight chaunteclere,” that was to his “faire Pertelotte” so dear:— “His comb was redder than the fine corall, Embattled, as it were a castle-wall; His bill was black, and as the jet it shone; Like azure were his legges and his tone (toes); His nailes whiter than the lilie flour, And like the burned gold was his color.”