OTHER DEFENCES

(Photo: Road Block site. Donyatt, Somerset - Summer 2004)

ROAD BLOCK

Road Blocks were installed to deny enemy armoured vehicles the freedom of movement which would have allowed them to move forward to their objectives quickly and maybe overrun the country in a short space of time. When we recall how the Nazi panzers raced across France, reaching and securing their objectives far faster than they themselves had previously thought possible, anything that might have delayed an enemy advance through Britain would have been a valuable asset to our defences.

A road block was built by installing two huge blocks of reinforced concrete, one each side of the road, with iron or steel girders slotted into place between them (similar to the rail block below). Another method was the vertical rail barrier, this consisted of lengths of steel rail which were inserted into steel sockets already concreted into the road surface. 'Hairpins' were barriers consisting of lengths of bent rail which were inserted into steel sockets in the road surface. The barriers would normally be removed by the troops on duty at the road block to allow normal traffic to move through and could be quickly re-inserted in an emergency. Any space either side of the barrier wide enough to drive a vehicle through would be blocked off with concrete cubes. Large areas of open ground either side of the barrier would usually be protected by an anti-tank ditch in order to stop vehicles by-passing the road block (this would normally be the case in the countryside). Other defences such as pillboxes or spigot mortar pits would be positioned nearby to give covering fire to the road block.

(Photo: Rail Block structure with 'closed top' barrier slot. Old GWR track, Donyatt, Somerset - Summer 2004)

RAIL BLOCK

The Rail Block was designed to stop enemy armoured vehicles, which had been denied the use of the roads, travelling along railway tracks. Although the surface would not be as fast as that of a road, the rail track would have been preferable to the hard slog through the hedgerows of the countryside.

The rail block consisted of two massive blocks of reinforced concrete, each standing on a huge concrete base, with the large slots on the inner faces of the structures facing towards each other across the width of the railway track. When being prepared for action, one end of an iron or steel girder would be placed into the 'closed top' slot of the first structure of the rail block and the other end of the girder would be lowered down into the 'open top' slot of the second structure - on the other side of the track. This procedure would be repeated until sufficient girders were in place. To prevent the girders being lifted out, a long locking pin, or bolt, would be inserted into a channel in the upper side of the open topped structure, passing all the way through the structure and above the girders, before being secured on the far side. As with the road block, cubes and/or anti-tank ditches would be used to block off any gaps either side of the rail block which were wide enough for vehicles to get through.

(Photo: Rail Block structure with 'open top' barrier slot. Old GWR track, Donyatt, Somerset - Summer 2004)

(Photo: Cube at Road Block site. Ruishton, Somerset - Winter (Feb) 2004)

ANTI-TANK CUBE

Constructed from concrete and designed to stop enemy armoured vehicles, the Cube fulfilled many tasks e.g. blocking gaps around defensive positions and forming barriers in certain vulnerable locations such as the exit points from beaches, etc. Cubes were constructed in two sizes, 3.5 foot and 5 foot. Some, depending on their task, were equipped with a metal bracket which was inserted into the top of the Cube and to which barbed wire could be attached.

(Photo: Dragon's Teeth. Fordgate, Bridgwater & Taunton Canal, Somerset - Spring 2003)

DRAGON'S TEETH

Dragon's Teeth (or 'Pimples') were constructed from concrete and have a square base with sloping sides that meet centrally at the apex. Tracked vehicles that attempted to drive over them would have exposed their vulnerable undersides to the fire of the defenders.

(Photo: Anti-Tank Posts. North of Chard Reservoir, Somerset - Summer 2004)

ANTI-TANK POSTS

Anti-tank posts, which were constructed from reinforced concrete, were installed at close intervals, in lines, and the posts were angled toward the expected direction of enemy attack. Situated along the top of railway embankments they were meant to halt the slow progress of enemy tanks attempting to climb up the steep side of the embankment onto the railway track. The posts were one of the less common types of anti-tank obstacle but on certain sections of the Taunton Stop Line they can be seen running along the top, western side, of railway embankments.

(Photo: Anti-Tank Wall. Victoria Avenue, Chard, Somerset - Summer 2004)

ANTI-TANK WALL

Anti-Tank Walls were the largest of the concrete anti-tank obstacles. Across the U.K. they differed in size and their method of construction - although the main construction material was concrete. Some were built by placing concrete blocks onto a concrete base and then infilling these with more concrete, others were existing walls which were fortified with concrete and some were built from stone. Their dimensions vary depending on where they were built and the job they were expected to do. Among many other tasks, they were used to block off roads and block harbour and beach exits. The walls usually had one or more gaps of approx. eighteen inches to allow pedestrians to pass through.

(Photo: Demolition Chamber. Lower Maunsel Lock, Bridgwater & Taunton Canal, Somerset - Spring 2003)

DEMOLITION - CHAMBER

As part of the overall plan to deny freedom of movement to the enemy, all permanent bridges along the Bridgwater & Taunton Canal were mined with Demolition Chambers. Wooden bridges were dismantled. In the photo above you can see four of the chambers, three now covered over with weed, which would have contained explosive charges.

(Photo: Defence Post. Supply Reserve Depot, Norton Fitzwarren, Somerset - Winter (Jan) 2004)

DEFENCE POST

These structures were built to protect important installations, e.g. Ordnance Factories, Supply Depots, etc. The lower section of the post was built of brick, the centre section of reinforced concrete and the upper section of brick. There are four very wide embrasures, one in each side of the centre section. The post has a low level protected entrance and on the outside of the upper section there is a bracket to which telephone wire was once attached. The open upper section of the post, which was reached by an outside fixed ladder, was probably used as a light anti-aircraft position for defence against low flying enemy aircraft. Some variants of the Defence Post did not have an upper section.

(Photo: Spigot Mortar position. Nothe Fort, Weymouth, Dorset - Summer 2004)

SPIGOT MORTAR

Along with the heavy weapons, anti-tank guns, tracked and non-tracked vehicles lost by the British Expeditionary Force (BEF) before and during the evacuation of Dunkirk, a great amount of smaller armaments were also lost. These included a large number of Vickers Medium Machine Guns, thousands of Bren Light Machine Guns and over one hundred thousand Lee Enfield Rifles plus huge amounts of ammunition. With the expected Nazi invasion of Britain imminent, it was crucial that as many armaments as possible were produced in the shortest possible time to re-equip the returning troops of the BEF and the troops of the Home Army.

The 29mm Spigot Mortar, also called the 'Blacker Bombard' after it's designer, Lieutenant Colonel Blacker, was developed as a relatively cheap weapon that could be mass-produced. This mortar dispensed with the expensive conventional mortar barrel, using a steel rod, or 'spigot', instead. The long, hollow, tail-boom of the projectile, the upper end of which contained an explosive charge, was designed to ensure a tight fit when loaded onto the spigot. The mortar's firing mechanism drove the spigot up inside the tail of the projectile, detonating the explosive charge which in turn propelled the projectile off the spigot and on towards it's target. The brief contact between the spigot and the tail of the projectile, plus the stabilising effect of the projectile's tail fins, were enough to give directional stability. The recoil from the exploding charge forced the spigot back into it's housing, thus compressing the spring and re-cocking the weapon.

The mortar could fire an anti-tank projectile with a 20lb warhead or an anti-personnel projectile with a 14lb warhead. There are differing accounts regarding the maximum range of the projectiles, however, the general view is that the maximum effective range of the anti-tank projectile was approx.100 yards. The weapon was mobile, with it's 4 legged portable mounting, but was mainly deployed for use in the static role in specially constructed pits which were positioned along the expected path of enemy advance. In the middle of each pit a large concrete pedestal was installed, a stainless steel pivot, or 'pin', was inserted into the top of the pedestal and the mortar was mounted onto the pin. This weapon, however, was not ready for service until 1941 when it was issued to the Home Guard and airfield defence forces and then remained in service until 1944.

(Photo: 6 pounder Hotchkiss Anti-Tank Gun Emplacement. Curry Mallet, Somerset - Spring 2003)

6 POUNDER ANTI -TANK GUN EMPLACEMENT

The loss of virtually all the British Expeditionary Force's armaments during the evacuation of Dunkirk left the Home Army with very few anti-tank guns so other weapons had to be found to plug the gap. Fortunately, in February 1940, the Army had ordered the reconditioning of 400 WWI vintage 6 pounder Hotchkiss guns as part of it's re-armament program - this order was subsequently increased to a total of 621 guns. As they came into service, the guns were mounted in reinforced concrete emplacements, or open concrete gun-pits, along the expected route of enemy attack.

(Photo: Beach Defence Battery. Seaton, Devon - Spring 2004)

BEACH DEFENCE BATTERY

These structures were built to defend the beaches around Great Britain from invading armoured vehicles and troops. The Hotchkiss 6 pounder anti-tank gun was mounted in many of these batteries. The main frontal embrasure of the battery pictured above has been bricked up.

(Photo: 6'' Coastal Defence Emplacement. Brean Fort, Somerset - Summer 2003)

COASTAL DEFENCE ARTILLERY BATTERY

During WWII many emergency coastal defence batteries were installed around Britain with most of these concentrated on the south and east coasts. In the south-west, at Brean Fort and on the islands of Steep Holm and Flat Holm, ex-naval guns were mounted in newly built emplacements covering the Bristol Channel approaches to Cardiff and Bristol. Brean Fort housed two 6'' guns, Steep Holm four 6'' guns and Flat Holm two batteries of twin 4.5'' dual purpose guns.

(Photo: CA Searchlight Emplacement. Nothe Fort, Weymouth, Dorset - Summer 2004)

COASTAL ARTILLERY SEARCHLIGHT

Searchlight emplacements were installed near coastal defence batteries during WWII to illuminate surface targets for the gunners. The emplacement in the above photograph was rebuilt and houses an original 90cm ex-AA searchlight complete with all it's equipment.

(Photo: Beach Light (CA Searchlight) emplacement. Sea-front, Seaton, Devon - Spring 2005)