But it is rather in parclose screens that this feature of excessive elongation is more especially in evidence. To counteract its ungainly appearance, without at the same time diminishing the extent of the aperture, resort is had in the principal screens at Chesterfield to the device of a transom to divide the fenestration about midway. This horizontal member, being feathered underneath, not only enhances the decorative character of the screenwork by the added effect of a lower tier of tracery-headed lights, but also makes for structural strength by providing a latitudinal junction from muntin to muntin. Another point of similarity between Derbyshire rood-screens and the typical midland screens at (_e.g._, at Somerton, in Oxfordshire; Blore, in Staffordshire; Wormleighton, in Warwickshire; and Strelley, in Nottinghamshire), and of divergence between the former and southern examples, is that, where the design comprises vaulting, the springing of the ribs is not necessarily in line with the cord or base of the pierced tracery of the bay-heads (as is practically the rule for it to be in Kent, Devonshire, and Somerset), but at a higher level, sometimes with a discrepancy of nearly two feet between the two levels. The result of this arrangement is not altogether happy. For traceried ornament that extends below the limits of a tympanum, failing to define the springing-point, tends to make the vaulting itself look dwarfed and curtailed. For the latter to show to best advantage, the ribs should have an obvious correspondence with the sweep of the fenestration arch from spring to crown. Wherever it is otherwise, a sense of lack of homogeneity between the parts cannot but be felt.