standing beneath one of the vaults and looking upward, you may read Roman numerals in order from I. to X., which prove their human origin well enough.  Next to their strength, regularity, and magnitude, the most astonishing point about this triple tier of arches, piled one above the other to a height of 180 feet above a brawling stream between two barren hills, is their lightness.  The arches are not thick; the causeway on the top is only just broad enough for three men to walk abreast.  So smooth and perpendicular are the supporting walls that scarcely a shrub or tuft of grass has grown upon the aqueduct in all these years.  And yet the huge fabric is strengthened by no buttress, has needed no repair.  This lightness of structure, combined with such prodigious durability, produces the strongest sense of science and self-reliant power in the men who designed it.  None but Romans could have built such a monument, and have set it in such a place—­a wilderness of rock and rolling hill, scantily covered with low brushwood, and browsed over by a few sheep—­for such a purpose, too, in order to supply Nemausus with pure water.  The modern town does pretty well without its water; but here subsists the civilisation of eighteen centuries past intact:  the human labour yet remains, the measuring, contriving mind of man, shrinking from no obstacles, spanning the air, and in one edifice combining gigantic strength and perfect beauty.  It is impossible not to echo Rousseau’s words in such a place, and to say with him:  ’Le retentissement de mes pas dans ces immenses voutes me faisait croire entendre la forte voix de ceux qui les avaient baties.  Je me perdais comme un insecte dans cette immensite.  Je sentais, tout en me faisant petit, je ne sais quoi qui m’elevait l’ame; et je me disais en soupirant, Que ne suis-je ne Romain!’

There is nothing at Arles which produces the same deep and indelible impression.  Yet Arles is a far more interesting town than Nismes, partly because of the Rhone delta which begins there, partly because of its ruinous antiquity, and partly also because of the strong local character of its population.  The amphitheatre of Arles is vaster and more sublime in its desolation than the tidy theatre at Nismes; the crypts, and dens, and subterranean passages suggest all manner of speculation as to the uses to which they may have been appropriated; while the broken galleries outside, intricate and black and cavernous, like Piranesi’s etchings of the ‘Carceri,’ present the wildest pictures of greatness in decay, fantastic dilapidation.  The ruins of the smaller theatre, again, with their picturesquely grouped fragments and their standing columns, might be sketched for a frontispiece to some dilettante work on classical antiquities.  For the rest, perhaps the Aliscamps, or ancient Roman burial-ground, is the most interesting thing at Arles, not only because of Dante’s celebrated lines in the canto of ’Farinata:’—­

  Si come ad Arli ove ’l Rodano stagna,
  Fanno i sepolcri tutto ’l loco varo;