Career
On 3 August 1846 Mary Cornelia Edwards married George Vane-Tempest, 5th Marquess of Londonderry. Sir John Edwards" Father was John Edwards (d1789) of Plas Machynlleth (also known as "Greenfields") Montgomeryshire, a Solicitor. He (John Edwards) acquired the Garth estate by his (3rd) marriage to Cornelia Owen, only child and heiress of Richard Owen.
The estate included the profitable Van lead mines, and was added to by purchase of parts of the Peniarth Estate along the Dyfi Valley.