Mr. Nikola Tesla, the great electrician, writes Dr. Thurston that he has been set back more than it even appeared at the first by his great misfortune; the fire which consumed his laboratory having left him even less material than had been at first thought and the results of the loss having more serious and far-reaching effect upon his progress. He is steadily working to repair this loss; but is not able to do all that he would wish or to sustain as prolonged application as formerly. Ambition and courage still remain, however, and his labors neither cease nor relax.