The district of the clays is associated with peat beds. There is peat, or rather there was once peat all over Aberdeenshire, but the depth and extent of the beds are greatest where the clay bottom exists. A climate that is moist without being too cold favours the growth of peat and the Buchan district, projecting so far into the North Sea and being subject to somewhat less sunshine than other parts of the county, provides the favouring conditions. The rainfall is only moderate but it is distributed at frequent intervals, and the clay bottom helps to retain the moisture and thus promotes the growth of those mosses which after many years become beds of peat. These peat beds for long provided the fuel of the population. In recent years they are all but exhausted, and the facility with which coals are transported by sea and by rail is gradually putting an end to the “casting” and drying of peats. Moraines of rough gravel—the wreckage of dwindling glaciers—are found in various parts of the Dee valley. The soil of Deeside has little intermixture of clay and is thin and highly porous. It follows that in a dry season the crops are short and meagre. The Scots fir, however, is partial to such a soil, and its ready growth helps with the aid of the natural birches to embellish the Deeside landscape. In the Cairngorms brown and yellow varieties of quartz called “cairngorms” are found either embedded in cavities of the granite or in the _detritus_ that accumulates from the decomposition of exposed rocks. The stones, which are really crystals, are much prized for jewellery, and are of various colours, pale yellow (citrine), brown or smoky, and black and almost opaque. When well cut and set in silver, either as brooches or as an adornment to the handles of dirks, they have a brilliant effect. Time was when they were systematically dug and searched for, and certain persons made a living by their finds on the hill-sides; but now they are more rare and come upon only by accident. 7. Natural History.