of drainage ditches. The railway line crosses it again, before it reaches Ruyton-XI-Towns, where there is a large loop around higher ground to the east. The river is crossed by Platt Mill Bridge, designed and built in 1791 by Edward Cureton, although also attributed to Thomas Telford. The river forms the border between civil parishes at this point, and so one half of the bridge is in Ruyton-XI-Towns, while the other is in Baschurch. The bridge has two arches, and is a grade II listed structure. A circular toll-house, built of red sandstone with a conical slate roof, was erected in the late eighteenth or early nineteenth century close to the bridge, and is now used as a house. Continuing to the south-west of Baschurch, Milford Bridge is another two-arched structure, which carries the Baschurch to Little Ness road over the river. It was designed by Thomas Stanton in 1831, and was built by Nathaniel Edwards. Stanton was the civil engineer Thomas Telford's deputy at the time, when Telford was the County Surveyor of Bridges for Shropshire. The river passes along the south-western edge of Yeaton Peverey parkland, to reach Forton Heath, where there is a bridge with a single elliptical arch, built in the early nineteenth century, which carries the Mytton to Forton road. Below the bridge, the river joins the River Severn, close to the contour. The junction is not far from Shrewsbury, but the course of the Severn is much longer, as it flows around several large meanders to reach the town. Hydrology The river rises on the edge of the North Shropshire sandstone plain, but for most of its length, the underlying rock is Bunter Sandstone. A series of streams converge to the east of Gobowen, which have risen further to the west at heights of up to . Initially, the streams are stony-bottomed, but this is soon replaced by clays and alluvial silts. Near Rednal, the flow is augmented by the Tetchill Brook, which starts as an outflow from a large mere at Ellesmere. The outflow was a Victorian solution to control the levels of the mere. It is joined by Newnes Brook, which drains sandstone-based soils between Ellesmere and Gobowen. Below the junction the river crosses Baggy Moor, a large basin which was filled with peat, but which has been extensively drained to enable it to be used for agriculture. Prior to 1777, it