completed on 9 July. The following day she was alerted to prepare for a test mobilisation in lieu of the annual fleet manoeuvres as part of the British response to the July Crisis. The mobilisation was ordered on 15 July, and the fleet was reviewed two days later at Spithead after which it conducted exercises. First World War At the beginning of the First World War, Bulwark and the 5th BS were based at Portland and assigned to the newly reformed Channel Fleet to defend the English Channel. After covering the safe transportation of the British Expeditionary Force to France in August, the 5th BS remained in Portsmouth until 4 September when they returned to Portland. They stayed there through October aside from exercises. From 5 to 9 November, Bulwark hosted the court martial of Rear-Admiral Sir Ernest Troubridge for his actions during the pursuit of the German battlecruiser and light cruiser in the Mediterranean Sea in August. On 14 November, the 5th BS was transferred to Sheerness because of concern that a German invasion of Great Britain was in the offing. Explosion A powerful internal explosion ripped Bulwark apart at about 07:53 on 26 November while she was moored at Number 17 buoy in Kethole Reach, west of Sheerness in the estuary of the River Medway. All the ship's officers were killed in the explosion and only a dozen ratings survived. A total of 741 men were lost, including members of the band of the gunnery school, HMS Excellent, which was playing aboard. Only about 30 bodies were recovered after the explosion. In terms of loss of life, the incident remains the second most catastrophic accidental explosion in the history of the United Kingdom, exceeded only by the explosion of the dreadnought battleship , caused by a stokehold fire detonating a magazine, at Scapa Flow in 1917. A naval court of enquiry into the causes of the explosion that was held on 28 November ruled out external explosions such as a torpedo or a mine because eyewitnesses spoke of a flash of flame near the aft turret and then one or two explosions quickly following, not the towering column of water associated with explosions against the outer hull. The gunnery logbook, recovered partially intact, and the testimony of the chief gunner's clerk, as well as several other survivors, said the six-inch ammunition magazines were being restowed to keep the