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2 three will tell you that it is a very interesting country.

The rocks of Wales are older and harder than the rocks of the plains;and as you travel from the south to the north, the older and harder they become. The highest mountains of Wales, and some of its hills,have crests of the very oldest and hardest rock—granite, porphyry,and basalt; and these rocks are given their form by fire. But the greater part of the country is made of rocks formed by water—still the oldest of their kind. In the north-west, centre, and west—about two-thirds of the whole country,—the rocks are chiefly slate and shale; in the south-east they are chiefly old red sandstone; in the north-east, but chiefly in the south, they are limestone and coal.

Its rocks give Wales its famous scenery—its rugged peaks, its romantic glens, its rushing rivers. They are also its chief wealth—granite, slate, limestone, coal; and lodes of still more precious metals—iron, lead, silver, and gold—run through them.

The highest mountain in Wales is Snowdon, which is 3,570 feet above the level of the sea. For every 300 feet we go up, the temperature becomes one degree cooler. At about 1,000 feet it becomes too