Read it through once

But being now interrupted, he put up the image; and pretty soon, going to the table, took up a large book there, and placing it on his lap began counting the pages with deliberate regularity; at every fiftieth page—as I fancied—stopping a moment, looking vacantly around him, and giving utterance to a long-drawn gurgling whistle of astonishment. He would then begin again at the next fifty; seeming to commence at number one each time, as though he could not count more than fifty, and it was only by such a large number of fifties being found together, that his astonishment at the multitude of pages was excited.