Monday, 7 March 2016

The Porch

The doorway to the porch

Moving anti-clockwise around the tower, the porch is the next interesting feature at St. Helen’s church and the current guide shows that it was built in the 15th century, with the later addition of the south aisle.

Looking at the porch and south aisle together, however, the walling appears to be very uniform – in colour, texture, weathering, block size and tool marking - and the masonry is bonded together. Compared to the stonework in the tower, the levels have been much more carefully set out and it provides a good example of the use of “Rotherham Red” sandstone for ashlar work.

General views of the porch

The degree of weathering to the sandstone exposed on the 3 elevations of the porch varies and, in places, softer beds have been scoured away and deeply eroded. Along with the tower, it has been subjected to the south-westerly wind and rain since its construction and it was also fully exposed to the pollution from the Orgreave Coking Works, before this site was closed down.

Details of the porch roof and sundial

The coping stones and the ridge stones to the plain tiled roof covering, which is quite recent, are uniformly weathered and blackened and they would appear to be original, with the only stone renewal being to the cuboid apex finial, upon which is set a sundial of unknown date.

A detail of the limestone arch
Although the large square block is of Rotherham Red sandstone – a variety that is slightly purple in colour – it is not possible to identify the provenance of the other stones used in its construction, without the benefit of a much closer inspection.

The pointed arch to the doorway of the porch is built of limestone, which an examination with a hand lens will confirm as an oolitic limestone of Jurassic age; however, it is quite unlike the dolomitic limestone of Permian age that is seen in the tower and possesses very different weathering characteristics - especially its chemical resistance to acid rain.

Installed as part of one of two phases of restoration undertaken during the later part of the 19th century, the renewed arch retains the old Rotherham Red sandstone hood moulding, complete with carved head stops that have nearly eroded away.

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