Then we are given the legend that accounts for it. Here Hercules fought
against the Ligurians, when the son of Jove, having exhausted his arrows,
was supplied with artillery by a discharge of stones from the sky, showered
on his enemies by Jupiter.

This desert, a little Sahara in Europe, occupies 30,000 acres. "It is
composed entirely of shingle," says Arthur Young, "being so uniform a mass
of round stones, some to the size of a man's head, but of all sizes less,
that the newly thrown up shingle of a seashore is hardly less free from
soil; beneath these surface-stones is not so much a sand as a cemented
rubble, with a small admixture of loam. Vegetation is rare and miserable,
some of the absinthium and lavender so low and poor as scarcely to
be recognised, and two or three miserable grasses, with _Centaurea
calycitropes_ and _solstitialis_, were the principal plants I could
find." A mineralogical examination of the rolled stones presents peculiar
interest. In the Little Crau, the mouth of the Durance, are found
prodigious numbers of green and crystalline rocks, granite and variolite
brought down from the Alps of Briancon, but nine-tenths of the pebbles of
the Great Crau are white quartz brought from the great chain of the Alps,
together with mica-slate and calcareous stones, and only a few of the
variolites of Mont Genevre. One may say that the Great Crau is a complete
mineralogical collection of all the rocks that form the chain of the Alps,
whence flow the Rhone and its tributaries.

The aspect of the Crau is infinitely desolate, but it is no longer as
barren as it was formerly. It is in fact, undergoing gradual but sure
transformation. This is due to a gentleman of Provence, named Adam de
Craponne, born in 1525 at Salon, who conceived the idea of bringing some
of the waters of the Durance through the gap where some of its overspill
had flowed in the diluvial epoch, by a canal, into the Great Crau, so that