The abundance of metaphorical expressions even in common language, indicates the numerous resemblances between the living and inorganic worlds. Description and poetry are full of imagery. A metaphor implies a resemblance between objects, a simile suggests it, and a comparison states it. [Illustration: THE DIONÆA, OR VENUS’S FLY-TRAP.] Thus to the human mind, the different departments of nature seem to reflect a light and beauty upon each other, even as the “earth-shine” lights the moon in the absence of the sun. The sky is a dome; the groves are temples; the sea moans and roars; the falling cataracts laugh and shout, and the calm lake is the smile of the Great Spirit. “Language,” says Dean Trench,[5] “is fossil poetry.” “Architecture is frozen music.” Many of the forms of art and devices of human invention have been suggested by Nature. The Doric column was borrowed from some stately tree shaft. The ornamented capital of the Corinthian column was decorated by carved copies of the graceful acanthus leaves. Gothic architecture found its models in the tree tops of the arching forests. [Illustration: A HUMAN HEART, SHOWING CHAMBERS AND VALVES.] Every experimenter in science is simply one who is inquiring of Nature for her analogies, truths, forms, forces, and machines; and like the wise and good mother that she is, she has granted many a pregnant suggestion to the busy brains of discoverers and inventors. [Illustration: THE NEPENTHES,[6] A PITCHER PLANT OF THE INDIAN ARCHIPELAGO.] MOVEMENTS OF PLANTS. Plants in their action illustrate many of the principles of natural philosophy, as if directed by intelligence. Turn their roots upward in the soil, and they will invariably turn down to the moisture. Bend their stems to the earth and they will seek to mount upward. The young sunflower greets the sun at his rising, and turns to behold his setting. Unwind a twining vine, and wind it in an opposite direction, and it will soon assert its right to assume its own method. Some plants shrink from touch; others, like the Venus fly-trap,[7] hold out their open palms to catch flies; many sleep; most seem to select special places, seasons, and conditions. They seem almost, at times, to be possessed of moral qualities. They adapt themselves to situations. If the season is dry, they are sparing of moisture; if the soil is scanty, they penetrate deeper for sustenance; if the winds are fierce, they grow strong by struggle; if gashed or broken, they have “philters for healing;” if pruned and chastened, they yield richer fruitage. [Illustration: SKELETON OF A FROG.—A GOOD SET OF SPRINGS.] One can not help feeling that certain trees have a personality. They are friendly with their shade. They are proud in their loftiness, confident in their strength, satisfied in their usefulness.