As the price of complete commercial systems for freeze-drying, of useful working capacity, exceeded budgetary limitations an apparatus was made from readily available parts which eliminated constructional problems and allowed of modifications and improvements. 1. THE EQUIPMENT When the Ulster Museum took formal responsibility for the conservation of the material from the wreck of La Trinidad Valencera in 1978 the author's laboratory was faced with the treatment of large amounts of waterlogged organic material from both recent and previous excavations. After consideration it was decided to start conservation using chemical dehydration and impregnation processes, but to acquire, as soon as possible, freeze-drying equipment for the speedy and effective processing of the small to medium-sized objects. Estimates from manufacturers in Britain and Europe for a system with a sublimation chamber of useful size showed that such proprietary systems were too expensive and it was thus necessary to devise a system which fell within the budget allowed. A design based on standard components available from engineering and scientific suppliers was produced for consideration, together with preliminary estimates of costs. Upon inquiry Edwards High Vacuum Limited of Crawley, Sussex, seemed able to supply most of the components and the design was submitted to them for final costing and evaluation of its feasibility. The only non-standard item was the stainless steel sublimation chamber (Fig. 1) Clamping Bolt Lifting Brackets Exhaust Port 4 used Vr'IJ