Xlii PROCEEDINGS—PERTHSHIRE SOCIETY OF NATURAL SCIENCE. 
geological effects produced by these meteorological conditions. On 
the one hand, although a small army of labourers had been employed 
for several months in repairing the damage caused by the flooding 
in early spring, yet traces had been left which will serve as memorials 
of the occurrence for years to come. Fields have been stripped of 
their fertile soil in places, others have been coated with silt and 
shingle, and banks have had large slices permanently eaten out of 
them. So much for the effect of the excess of moisture and its 
augmented transporting power. On the other hand, the recent lack 
of moisture has left its mark on the surface of the land also. One 
effect has been the accumulation, on the higher ground, of an 
enormous quantity of finely pulverised detritus, which would, under 
normal conditions, have been washed off by the rains, and carried 
by the streams on to the valley floors. Owing to the absence of rain 
this material remained on the fields and roadways as a fine silicious 
and micaceous coating, sometimes reaching a thickness of from one 
to two inches in depth, which is apt to be carried by the wind into 
unexpected quarters. 
These observations may seem trivial in themselves, but they 
have an important bearing on certain geological problems. The 
geologist is constantly being assailed with the objection that the 
processes by which he asserts the earth’s crust has been built up 
are so imperceptibly slow in their operation that they demand an 
extension of time which neither practical science nor common sense 
are disposed to grant. The force of this argument, however, dis¬ 
appears when we see what changes can be effected by the operation 
of Nature’s laws on the small portion of the earth’s surface within 
our observation in the course of a few months, or even one night. 
The subject of the disintegration of rock surfaces, and its bearing 
on the origin of soils, is one to which I hope to return on some 
future occasion. 
Not only on the inorganic world, however, have these meteoro¬ 
logical conditions left their mark. Vegetation has been affected to 
an equal extent, though in a different way. In the middle of summer 
it was a matter of common observation and comment that most of 
the trees, such as the oaks, limes, elms, etc., had their branches 
tipped with tufts of leaves of a much lighter hue than the mass of 
the foliage, indicating a subsequent young growth. This was seen 
most conspicuously of all in the copper beeches, which were orna¬ 
mented with tassels of bright red leaves, standing out against a 
sombre background of purple and brown. This, I am inclined to 
think, was caused by the ascent of the sap in the vessels of the trees 
having been arrested by the sudden and severe frost of early spring, 
and its subsequent resumption on the advent of more genial condi¬ 
tions. This would give rise to a first or normal growth of foliage 
followed by a modified second growth, with a distinct break between 
the two. It has, I believe, been feared by some foresters that 
the young wood formed during this second growth would not have 
time to ripen before being checked by the frosts of early winter, 
and that permanent injury might thus befall many of the trees. 
Whether this fear is well grounded or not remains to be seen when 
