lion upon the lake of
Geneva and the valley of the Rhone about Villeneuve and Aigle. If so,
you can understand from personal knowledge the first great stage in the
mud-filling process; for you must have observed for yourself from that
commanding height that the lake once extended a great deal farther up
country towards Bex and St. Maurice than it does at present. You can
still trace at once on either side the old mountainous banks,
descending into the plain as abruptly and unmistakably as they still
descend to the water's edge at Montreux and Vevey. But the silt of the
Rhone, brought down in great sheets of glacier mud (about which more
anon) from the Furca and the Jungfrau and the Monte Rosa chain, has
completely filled in the upper nine miles of the old lake basin with a
level mass of fertile alluvium. There is no doubt about the fact: you
can see it for yourself with half an eye from that specular mount (to
give the Devil his due, I quote Milton's Satan): the mud lies even from
bank to bank, raised only a few inches above the level of the lake, and
as lacustrine in effect as the veriest geologist on earth could wish
it. Indeed, the process of filling up still continues unabated at the
present day where the mud-laden Rhone enters the lake at Bouveret, to
leave it again, clear and blue and beautiful, under the bridge at
Geneva. The little delta which the river forms at its mouth shows the
fresh mud in sheets gathering thick upon the bottom. Every day this new
mud-bank pushes out farther and farther into the water, so that in
process of time the whole basin will be filled in, and a level plain,
like that which now spreads from Bex and Aigle to Villeneuve, will
occupy the entire bed from Montreux to Geneva.

Turn mentally to the upper feeders of the Po itself, and you find the
same causes equally in action. You have stopped at Pallanza--Garoni's
is so comfortable. Well, then, you know how every Alpine stream, as it
flows, full-gorged, into the Italian lakes, is busily engaged in
filling them up as fast as ever it can with turbid mud from the
uplands. The basins of Maggiore, Como, Lugano, and Garda are by origin
deep hollows scooped out long since during the Great Ice Age by the
pressure of huge glaciers that then spread far down into what is now
the poplar-clad plain of Lombardy. But ever since the ice cleared away,
and the torrents began to rush headlong down the deep gorges of the Val
Leventina and the Val Maggia, the