Moxon was speaking with unusual animation and earnestness. As he paused I heard in an adjoining room known to me as his “machine-shop,” which no one but himself was permitted to enter, a singular thumping sound, as of some one pounding upon a table with an open hand. Moxon heard it at the same moment and, visibly agitated, rose and hurriedly passed into the room whence it came. I thought it odd that any one else should be in there, and my interest in my friend—with doubtless a touch of unwarrantable curiosity—led me to listen intently, though, I am happy to say, not at the keyhole. There were confused sounds, as of a struggle or scuffle; the floor shook. I distinctly heard hard breathing and a hoarse whisper which said “Damn you!” Then all was silent, and presently Moxon reappeared and said, with a rather sorry smile: “Pardon me for leaving you so abruptly. I have a machine in there that lost its temper and cut up rough.” Fixing my eyes steadily upon his left cheek, which was traversed by four parallel excoriations showing blood, I said: “How would it do to trim its nails?” I could have spared myself the jest; he gave it no attention, but seated himself in the chair that he had left and resumed the interrupted monologue as if nothing had occurred: “Doubtless you do not hold with those (I need not name them to a man of your reading) who have taught that all matter is sentient, that every atom is a living, feeling, conscious being. _I_ do. There is no such thing as dead, inert matter: it is all alive; all instinct with force, actual and potential; all sensitive to the same forces in its environment and susceptible to the contagion of higher and subtler ones residing in such superior organisms as it may be brought into relation with, as those of man when he is fashioning it into an instrument of his will. It absorbs something of his intelligence and purpose—more of them in proportion to the complexity of the resulting machine and that of its work. “Do you happen to recall Herbert Spencer’s definition of ‘Life’? I read it thirty years ago. He may have altered it afterward, for anything I know, but in all that time I have been unable to think of a single word that could profitably be changed or added or removed. It seems to me not only the best definition, but the only possible one. “‘Life,’ he says, ‘is a definite combination of heterogeneous changes, both simultaneous and successive, in correspondence with external coexistences and sequences.’” “That defines the phenomenon,” I said, “but gives no hint of its cause.”