He was voyaging backward into time! So strange a thing--and so simple in fundamental conception. He recalled how his grandfather had explained it, back in the laboratory. Everything had been created at once. On the scroll of time everything is permanent. We live our infinitesimal lifetime progressing forward through ordained, predetermined events. All the past and all the future exist--but we can only be aware of that forward-moving instant which we call the present. And old Professor Dane's fundamental conception--certainly it could now be considered finally proven, with his grandson actually applying it to really travel through time. He had thought that all material things, strewn in sequence on the scroll of time, were of different physical characteristics. Different states of matter; a different vibration-rate, so that to change the vibratory frequency of any object would be to change its position on the time-scroll! * * * * * Alan had started from his grandfather's laboratory, near Riverside Drive in mid-town New York. The date had been May of 1942. His watch, set above the other time-recording instrument on his wrist, told him that his start had been made only a scant half hour before, by his personal consciousness of time. How long ago--how far away that seemed now! There had been a reeling of his senses, the soundless clapping of swiftly alternating light and darkness at the shadowy laboratory windows. Then as his rate of change accelerated, the days and nights had merged into this flat, dead emptiness of gray. Then the house had abruptly dwindled, thinned out, and disappeared from around him! He had reached a time-era before its construction. Still with greater speed, the shadowy shifting outlines of the great city were in motion, shrinking into smaller and smaller buildings, narrower, shorter roads. More shadowy open spaces appeared, then were replaced by towering giants of trees. 1850 he reached and passed--then 1800, and 1750. The city had been long gone by then--the little village of British New York was a shrunken settlement of a few thousand persons clustered down about the Battery, four miles from where Alan Dane was. He could see that he was poised now on what seemed a little wooded hill, sloping down to the broad Hudson River a few hundred feet away. It was a strange transition indeed. And yet to Alan Dane, the strangeness of his own emotions seemed not the least of it. Three years of his life had passed since that night when he had promised his grandfather he would carry on the experiments--three years in which he had lost his grandfather, but gained a wife and son. Ruth Vincent had married him and together they had worked on the fragile thing that he bore now on his back--fragile, but more potent in a strange, incredible way than any other device.