As a fair proof of the mild and salubrious nature of the atmosphere, we need only observe that the magnolia, the myrtle, and other delicate exotics, not only live but flourish in this auspicious climate. Equally favourable to health and longevity, this district has numerous living testimonies in the vigorous health and protracted age of its inhabitants, who are fully sensible of the blessings they enjoy. The valley, at its greatest breadth, measures about eighteen miles; in various places, however, it is contracted into less than the half of this space, and presents in its outline a constant variety of picturesque and graceful windings. The town of Cardiff is built on the eastern bank of the river Taff, over which there is a handsome bridge of five arches, leading to Swansea. It is a thriving town, possessing considerable trade; and, by means of a canal from Pennarth to Merthyr-Tydvil, has become the connecting medium between these extensive iron-works and the English market, and is, in fact, the port of the latter. The Taff, which falls into the sea at Cardiff, forms a principal outlet for the mining districts of Glamorganshire, the produce of which has hitherto found its way to market through the Glamorganshire canal; but its sea-lock, constructed about fifty years ago, has long been found inadequate to the demands for increased accommodation, in consequence of the great prosperity of trade since the canal was opened. The Marquess of Bute, possessing lands in this neighbourhood, obtained, in 1830, an act for constructing a new harbour, to be called the Bute ship-canal, and completed the work at his own expense. The great advantages of this enterprise are--a straight, open channel from Cardiff-roads to the new sea-gates, which are forty-five feet wide, with a depth of seventeen feet at neap, and thirty feet at spring-tide. On passing the sea-gate, vessels enter a capacious basin, having an area of about an acre and a half, sufficient to accommodate large trading-vessels and steamers. Quays are erected along the side of the canal, finished with strong granite coping, and comprising more than a mile of wharfs, with ample space for warehouses, exclusive of the wharfs at the outer basin. This great work was finished in the summer of 1839, at an expense to the proprietor of three hundred thousand pounds. Cardiff Castle, which stands insulated on a high mound of earth, was partially restored and modernised by the late Marquess of Bute. This ancient fortress is connected with several interesting events in history. In one of its towers, or dungeons, Robert Duke of Normandy was twenty-five years imprisoned by his younger brother, Henry the First, who had previously usurped the throne and deprived him of his eyesight. In the reign of Charles the First it was bombarded by the Parliamentary forces during three successive days, and only surrendered in consequence of treachery on the part of the garrison. [Illustration: GLOUCESTER.] GLOUCESTER.