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 mud has been hard at work, doing its level best to fill those great ice-worn bowls up again. Near the mouth of each main stream it has already succeeded in spreading a fan-shaped delta. I will not insult you by asking you at the present time of day whether you have been over the St. Gothard. In this age of _trains de luxe_ I know to my cost everybody has been everywhere. No chance of pretending to superior knowledge about Japan or Honolulu; the tourist knows them. Very well, then; you must remember as you go past Bellinzona--revolutionary little Bellinzona with its three castled crags--you look down upon a vast mud flat by the mouth of the Ticino. Part of this mud flat is already solid land, but part is mere marsh or shifting quicksand. That is the first stage in the abolition of the lakes: the mud is annihilating them.