in the form of wrought iron serpentines. Prescient concerns began to be raised in the mid-1530s about whether the Camber might silt up further and ultimately become unusable as an anchorage. Concentric design, 1539–40 In 1539 the threat of invasion from France and Spain grew and Henry issued orders for his coastal defences to be improved, creating a sequence of fortifications called the Device Forts across England. These were intended to carry artillery pieces able to engage enemy naval vessels should they approach the coast, and to deter any enemy landings. As part of this programme of work, Camber Castle was considerably expanded at a cost of £5,660. The first phase of this work took place from 1539 until autumn 1540. The Moravian engineer Stefan von Haschenperg was responsible for the design of the fort, being paid the substantial salary of £75 a year for his work on this and other similar projects, including Calshot, Hurst, Sandgate and Sandown. Philip Chute, John Fletcher and William Oxenbridge, all prominent local men, served as the commissioners for the project, Oxenbridge becoming the pay master. Finding sufficient numbers of workmen was difficult and some had to be pressed into service unwillingly. More artillery pieces were sent to the castle ahead of the work being completed, and were probably installed in temporary battery positions around the castle site. Initially the old tower was converted into a stronger keep which was able to support artillery guns on its roof, a gatehouse was built alongside it, four stirrup towers – so-called because of their shape – a curtain wall was constructed around the outside of the castle, and bastions erected around the wall. Towards the end of this phase of work the castle was altered in a frantic burst of work, possibly driven on by pressure from the King himself. The height of the curtain wall was increased, the gatehouse extended into an entrance bastion, a new network of underground passages installed, and foreworks added around the outside of the bastions. By the end of 1540 the castle was garrisoned with 17 men and equipped with artillery, with Chute appointed as its captain. The result was a concentric fortress, which von Haschenperg had hoped would combine the best of Italian military architecture, able to carry heavy guns but with a low profile to protect against any incoming artillery fire. Various flaws rapidly became apparent. The castle's