When Thomas Embleton (from Horncliffe Mains)) died in 1915, The Mart was taken over by Wooler Auction Mart. In 1950, Wooler was run by A. Thompson and Son. Later it became a partnership of Thompson and Stewart, then Wooler Livestock Co. Ltd.
After the railways closed, Cornhill Mart was used as a workshop for making agricultural implements and repairs. That closed in 1980 and sadly, the octagonal building was demolished in 2010.
(Thanks to Cornhill Social history group for this information and photograph)