John Eldon & Sons was evidently a late nineteenth century cutlery maker.  The Hawley table knife is made from shear steel, with a xylonite handle.

Unfortunately, the company name does not apparently appear in any Sheffield directories of that (or any other) era.

One possibility is that the knife was made by John McClory & Sons, Eldon Street.  In The Sheffield Daily Telegraph, 7 August 1897, McClory’s issued an apology to Marsh Bros for infringing its ‘J. Milton’ mark (McClory’s by that date was based in Milton Street).  McClory’s stated that they used ‘J. Milton’ as a Second Mark (denoting cheaper quality), ‘in the same manner as we did ‘J. Eldon’, when we carried on business in Eldon Street’.