– from 6th Bn Royal Scots 227th (Haddingtonshire) Medium Bty (Howitzers) at Drill Hall, Dalmeny Street, Leith – from 8th Bn Royal Scots 228th (Peeblesshire and Midlothian) Medium Bty (Howitzers) at High Street, Dunbar – from 8th Bn Royal Scots (The Leith and Dunbar Drill Halls had previously belonged to the 7th Battalion, Royal Scots.) The CO (Lt-Col J.B. Cameron, DSO, TD) and senior major (E.G. Thompson, MC) of the new brigade were prewar officers of the 1st Lowland (City of Edinburgh) Hvy Bty. Affiliated to it were the cadet corps of North Berwick, Haddington, and Tranent Industrial School. The brigade served as 'Army Troops' in 52nd (Lowland) Divisional Area of Scottish Command. In 1924, the RGA was subsumed into the RA, and in 1938 RA brigades were redesignated as regiments. World War II Mobilisation When the TA was doubled in size after the Munich Crisis of 1938, the regiment split into two: 57th (Lowland) Medium Rgt Regimental HQ, 225 and 226 (City of Edinburgh) Btys at Edinburgh 66th Medium Rgt RHQ and 227 (Haddingtonshire) Bty at Prestonpans 228 (Peeblesshire and Midlothian) Bty at Leith Shortly after the outbreak of war, on 14 September 1939, 57th (Lowland) Medium Rgt was converted to the heavy artillery role at Leith, initially being designated 2nd Heavy Regiment, then 51st (Lowland) Heavy Regiment. It had A, B, C and D Heavy Batteries. 51st (Lowland) Heavy Regiment Battle of France At this time heavy regiments consisted of four 4-gun batteries, which in the 51st were designated A, B, C, and D. 51st (Lowland) Hvy Rgt would have been equipped with 6-inch guns (one Bty) and 9.2-inch howitzers (three batteries), both of World War I vintage. In November 1939, the newly converted regiment deployed to join the British Expeditionary Force in France under Lt-Col D. McDowell, who had been CO since 1936. On 10 May 1940, the Phoney War ended with the German invasion of the Low Countries, and the BEF followed the pre-arranged Plan D and advanced into Belgium to take up defences along the River Dyle. It was largely in position by 15 May and subject to German probing attacks. However, the Panzers of the Wehrmacht's Army Group A had broken through the Ardennes and threatened the BEF's flank, so on 16 May it began to withdraw to the River Escaut. On 17 May a gap opened up between the BEF and the Belgian