ILLUSTRATIONS.DEPARTURE FROM VIENNA.—FRANK'S LETTER.—A FAREWELL PROMENADE.—FROM VIENNA TO CRACOW.—THE GREAT SALT-MINE OF WIELICZKA, AND WHAT WAS SEEN THERE.—CHURCHES AND PALACES UNDERGROUND.—VOYAGE ON A SUBTERRANEAN LAKE.THE BOY TRAVELLERS
IN THE
RUSSIAN EMPIRE.