240 INUNDATIONS IN WINTER. 
the ground, it offers little mechanical resistance to superficial 
currents. If, under these circumstances, warm weather accom- 
panied by rain occurs, the rain and melted snow are swiftly 
hurried to the bottom of the valleys and gathered to raging 
torrents. 
It ought further to be considered that, though the lighter 
ploughed soils readily imbibe a great deal of water, yet grass- 
lands, and all the heavy and tenacious earths, absorb it in 
much smaller quantities, and less rapidly than the vegetable 
mould of the forest. Pasture, meadow, and clayey soils, 
taken together, greatly predominate over sandy ploughed fields, 
in all large agricultural districts, and hence, even if, in the case 
we are supposing, the open ground chance to have been thawed 
before the melting of the snow which covers it, it is already 
saturated with moisture, or very soon becomes so, and, of course, 
cannot relieve the pressure by absorbing more water. ‘The con- 
sequence is that the face of the country is suddenly flooded 
with a quantity of melted snow and rain equivalent to a fall of 
six or eight inches of the latter, or even more. This runs un- 
obstructed to rivers often still-bound with thick ice, and thus 
inundations of a fearfully devastating character are produced. 
The ice bursts, from the hydrostatic pressure from below, or is 
violently torn up by the current, and is swept by the impetu- 
ous stream, in large masses and with resistless fury, against 
banks, bridges, dams, and mills erected near them. The bark 
of the trees along the rivers is often abraded, at a height 
of many feet above the ordinary water-level, by cakes of float- 
ing ice, which are at last stranded by the receding flood on 
meadow or ploughland, to delay, by their chilling influence, the 
advent of the tardy spring. 
Another important effect of the removal of the forest shelter 
in cold climates may be noticed here. We have observed that 
the ground in the woods either does not freeze at all, or that if 
frozen it is thawed by the first considerable snow-fall. On the 
contrary, the open ground is usually frozen when the first 
spring freshet occurs, but is soon thawed by the warm rain 
