The vestibule mosaics are not easy to study, as the best are in the domes immediately overhead.  But they are very interesting in their simple directness.  Their authors had but one end in view, and that was to tell the story.  As thorough illustrations they could not be overpraised.  And here let me say that though Baedeker is an important book in Venice, and S. Mark’s Square is often red with it, there is one even more useful and necessary, especially in S. Mark’s, and that is the Bible.  One has not to be a very profound Biblical student to keep pace, in memory, with the Old Masters when they go to the New Testament; but when the Old is the inspiration, as chiefly here, one is continually at fault.

[Illustration:  ONE OF THE NOAH MOSAICS In the Atrium of S. Mark’s]

The vestibule mosaics are largely thirteenth century.  That is to say, they were being fixed together in these domes and on these walls when England was under the first Edwards, and long indeed before America, which now sends so many travellers to see them—­so many in fact that it is almost impossible to be in any show-place without hearing the American accent—­was dreamed of.

The series begins in the first dome on the right, with the creation of the world, a design spread over three circles.  In the inner one is the origin of all things—­or as far back as the artist, wisely untroubled by the question of the creation of the Creator, cared to go.  Angels seem always to have been.  In the next circle we find the creation of the sun, moon, and stars, birds, beasts, and fishes, and finally of man.  The outer circle belongs to Adam and Eve.  Adam names the animals; his rib is extracted; Eve, a curiously forbidding woman, rather a Gauguinesque type, results; she is presented to Adam; they eat the fruit; they take to foliage; they are judged; the leaves become real garments; they are driven forth to toil, Adam with an axe and Eve with a distaff.

On the sides is the story of Cain and Abel carried back to an earlier point than we are accustomed to see it.  Later, to the altar Cain brings fruit and Abel a lamb; a hand is extended from heaven to the fortunate Abel while Cain sulks on a chair.  The two brothers then share a sentry-box in apparent amity, until Cain becomes a murderer.

We next come, on the sides, to the story of Noah and the Tower of Babel.  Noah’s biography is vivid and detailed.  We see him receiving Divine instruction to build the ark, and his workmen busy.  He is next among the birds, and himself carries a pair of peacocks to the vessel.  Then the beasts are seen, and he carries in a pair of leopards, or perhaps pumas; and then his whole family stand by while two eagles are inserted, and other big birds, such as storks and pelicans, await their turn.  I reproduce this series.  On the other side the rains have begun and the world is drowning.  Noah sends out the dove and receives it again; the waters subside; he builds his altar, and the animals released from the ark gambol on the slopes of Ararat.  The third series of events in the life of Noah I leave to the visitor to decipher.  One of the incidents so captured the Venetian imagination that it is repeated at the eastern corner of the Ducal Palace lagoon facade.