Midland Railway (MR): Pilsley Branch Extension and Branches Land Plan Surveyed by P S McCallum, estate agent, Derby in 1913. Scale 2 chains: 1 inch. 12 sheets in volume. Produced by the Engineer's Office, Western Division, Derby Scale 2 chains: 1 inch Same folder contains: Plan of Blackwell branches and extension surveyed by W H C Clay, 1915 Plan of Alfreton Colliery branch, 1920. Front sheet for Alfreton Colliery and Morton branches, marked "not yet surveyed". Surveyor identified as W H C Clay, date given as 191 - leaving the final digit for completion later in the 1910s. 1913-1915