"I should add," continued Vaughn, ignoring my remarks, "that we have established rules to measure the force of gravitation, and have estimated the decrease of attraction as we leave the surfaces of the planets. We have made comparative estimates of the weight of the earth and planets, and have reason to believe that the force expression of gravitation attains a maximum at about one-sixth the distance toward the center of the earth, then decreases, until at the very center of our planet, matter has no weight. This, together with the rule I repeated a few moments ago, is about all we know, or think we know, of gravitation. Gravitation is the beginning and gravitation is the end; all earthly bodies kneel to gravitation. I can not imagine a Beyond, and yet gravitation," mused the rapt philosopher, "may also be an expression of--" he hesitated again, forgetting me completely, and leaned his shaggy head upon his hands. I realized that his mind was lost in conjecture, and that he was absorbed in the mysteries of the scientific immensity. Would he speak again? I could not think of disturbing his reverie, and minutes passed in silence. Then he slowly, softly, reverently murmured: "Gravitation, Gravitation, thou art seemingly the one permanent, ever present earth-bound expression of Omnipotence. Heat and light come and go, as vapors of water condense into rain and dissolve into vapor to return again to the atmosphere. Electricity and magnetism appear and disappear; like summer storms they move in diversified channels, or even turn and fly from contact with some bodies, seemingly forbidden to appear, but thou, Gravitation, art omnipresent and omnipotent. Thou createst motion, and yet maintainest the equilibrium of all things mundane and celestial. An attempt to imagine a body destitute of thy potency, would be to bankrupt and deaden the material universe. O! Gravitation, art thou a voice out of the Beyond, and are other forces but echoes--tremulous reverberations that start into life to vibrate for a spell and die in the space caverns of the universe while thou continuest supreme?" [Illustration: "SOLILOQUY OF PROF. DANIEL VAUGHN. 'GRAVITATION IS THE BEGINNING, AND GRAVITATION IS THE END; ALL EARTHLY BODIES KNEEL TO GRAVITATION.'"] His bowed head and rounded shoulders stooped yet lower; he unconsciously brushed his shaggy locks with his hand, and seemed to confer with a familiar Being whom others could not see.