The Royal Research Ship 'Discovery'. Part 15.

Making a Start on the Inner Hull

It is easy to be wise after an event as many of us will admit, and such was the case regarding the conservation of the inner hull of Discovery. During the late 1980s and early 1990s many features had been built in the inner hull to provide better visitor interpretation of their surroundings. These interpretations effectively enclosed parts of the inner hull of the ship, especially the starboard side. During the Full Structural Survey the surveyor was limited to how much of the inner hull he could survey without opening up these structures that had been built to provide a better visitor experience. Ideally they should have been opened up and re-built afterwards. However, finance was limited and only that which was affordable was surveyed. The Survey Report was noted to that effect. Now that the real work had started I had time and opportunity to do a more in-depth survey and had started while work was proceeding on the outer hull. In gaining access behind the interpretative structures I found damp and decay. How could this have happened? Easy! Cut off ventilation; moisture will collect and find unprotected timber surfaces that it will inhabit at will then decay and related fungi will result. A typical example of this was found in the Boiler-room of the ship and the following sequence of pictures amply illustrates the effect of enclosing spaces. A replica boiler had been built on the port side of this space and, since originally there had been two boilers, a mirrored structure had been built on the starboard side to give the illusion of a second boiler.

Boiler-room before mirror structure was removed.

During removal.

After removal revealing the dam and decay on the ships side
due to lack of ventilation.

The Engine Room of Discovery had remained virtually the same as it had been after the removal of the machinery during the Second World War. It was in a sad state, neglected but containing many interesting features that cried out to be seen, so it had been planned as part of the overall Project, to renovate the space and open it up to the visiting public. The space demonstrated the heavy structure of the Oak frames around the stern. Other features included the mechanism that allowed the crank-shaft from the engine to be disconnected from the propeller allowing the latter to be removed and hoisted up to deck level should repairs be needed, or if it needed to be protected from ice; there was the position where the distillation plant had operated; valves that controlled the access of sea-water to cool the engine; a structure supporting the base of the Mizzen Mast; the huge engine mountings. All were scheduled to be opened up, repaired, replaced, restored where possible and conserved. Given its condition, the work to be done had to reflect the history and use of the space and needed to be carefully carried out.

The Engine room space in the process of being restored.

The same space washed and drying out.

The schedule of work in the inner hull dictated that it should start in the engine-room and work forward in the lower holds of the ship. Ballast in the form of Pig Iron ingots was stacked between the bottom frames and the space under the Boiler-room was first to be opened up and where the extent of the freshwater ingress into the inner hull from the upper deck became apparent.

The depth of the fresh water allowed to accumulate is evidenced by the rust
coloured line on the ballast ingots that themselves are welded together by corrosion.

The first step was to dry the whole spaces out. Electric driers were hired and placed where they would be most effective. Humidity readings were taken at regular intervals and the moisture content of the damp timbers was monitored using non-evasive probes. Slowly the air and timber conditions improved. The opportunity was taken to lift the ballast ingots from where they were stowed, thoroughly clean and paint them with a protective coating. It was obvious that if the ingots were exposed to moist air or water again corrosion would result. Shrink wrapping, using a heavy polythene material, was the simple answer but not before the ballast spaced had been cleaned and treated with a proper protective coating.

Ballast stacked neatly and protected.

Next to the Engineroom was the Boiler-room I have already referred to. The replica boiler was a substantial structure with a tiny door built into its left side to allow entry into the inner boiler. Within this replica a ventilation unit had been placed 17 or 18 years previously. The damp conditions within had taken their toll and the unit had ceased to function some time before we gained entry. Another problem! This time one that had been anticipated during the planning stages of the Project. It had been obvious from the beginning that heating and ventilation of the inner hull had to be better controlled. It would have been ideal if a state of the art system could have been provided but that may well have compromised the declared intention to preserve as much of the original materials as was possible. Anyway, the bottom line was that financially we couldn't afford such a luxury. After much research and advice it was decided that portable, thermostatically controlled (fitted with a manual over-ride), individual, heating and dehumidifying units were the answer. These units would be placed throughout the inner hull and a system devised to remotely monitor the air conditions, so that alterations could be made to the settings on the units whenever the need arose.

Next. Further detail on the progress of the Project.