These are the 14
1 The London Electricity Board. The administrative County of London and parts of Essex, Kent, Middlesex and Surrey.
2 The South Eastern Electricity Board. Parts of Kent, Middlesex, Surrey and Sussex.
3 The Southern Electricity Board. Berkshire, Hampshire, the Isle of Wight, Wiltshire and parts of Buckinghamshire, Dorsetshire, Gloucestershire, Middlesex, Oxfordshire, Somersetshire, Surrey and Sussex.
4 The South Western Electricity Board. Cornwall (including the Isles of Scilly), Devonshire and parts of Dorsetshire, Gloucestershire (including Bristol) and Somersetshire.
5 The Eastern Electricity Board. Cambridgeshire, Hertfordshire, Huntingdonshire, the Isle of Ely, Norfolk, Suffolk and parts of Bedfordshire, Buckinghamshire, Essex, Middlesex, Oxfordshire and the Soke of Peterborough.
6 The East Midlands Electricity Board. Leicestershire, Northamptonshire, Rutland and parts of Bedfordshire, Buckinghamshire, Derbyshire, Lincolnshire, Nottinghamshire, the Soke of Peterborough, Staffordshire and Warwickshire.
7 The Midlands Electricity Board. Herefordshire, Worcestershire and parts of Gloucestershire, Oxfordshire, Shropshire, Staffordshire and Warwickshire (including Birmingham).
8 The South Wales Electricity Board. Brecknockshire, Carmarthenshire, Glamorganshire, Monmouthshire, Pembrokeshire, Radnorshire and part of Cardiganshire.
9 The Merseyside & North Wales Electricity Board. Anglesey, Caernarvonshire, Denbighshire, Flintshire, Merionethshire, Montgomeryshire and parts of Cardiganshire, Cheshire, Lancashire (including Liverpool) and Shropshire.
10 The Yorkshire Electricity Board. Parts of Derbyshire, Lincolnshire, Nottinghamshire and of the East and West Ridings of Yorkshire.
11 The North Eastern Electricity Board. Durham, Northumberland, the North Riding of Yorkshire and parts of the East and West Ridings of Yorkshire (including York).
12 The North Western Electricity Board. Cumberland, Westmorland and parts of Cheshire, Derbyshire, Lancashire (including Manchester) and of the West Riding of Yorkshire.
13 The South East Scotland Electricity Board. Berwickshire, Clackmannanshire, Fifeshire, Lothians, Peebles, Selkirkshire and parts of Dunbartonshire, Roxburghshire and Stirlingshire.
14 The South West Scotland Electricity Board. Ayrshire, Dumfries-shire, Kirkcudbrightshire, Lanarkshire, Renfrewshire, Wigtownshire and parts of Dunbartonshire, Roxburghshire and Stirlingshire