Volume Four - An Era of Change, Uncertainty, Depression & War - Some thoughts regarding the apparent reluctance of Pounds to remove the pontoon . . .

The description of its construction in the Engineer and with reference to Kempe’s Engineers Year Book earlier would however, suggest that it was possible to disconnect the pontoon transversely i.e. half way along its length (together with the associated radial arm booms) and dock one half on the other, piggy-back style, for maintenance purposes. I could’t comment if this ever occurred but do I recall that it was a rusty old hulk.

In normal use the pontoon’s twenty six internal compartments were filled with dock water each time a vessel was loaded or unloaded at the pontoon. I feel sure that internal cleaning and painting was unlikely to have occurred on a regular basis over its service life of c.50 years and the drawings do not show inspection hatches for the purpose.

Also we should not forget that this vessel would be subjected to large forces induced by the towing operation and of course waves impose their own peculiar forces on a flat bottomed vessel in open-sea.

I could also foresee the challenges that might ensue with the trim of the pontoon if it had been split into its two (or four) constituent parts prior to its trip to the breakers yard. I believe that the smaller section some 22’ – 0” (6.7m) wide had ballast installed on its deck on the port side running for 305’ -10¾” (93.2m). Was this to balance the superstructure and plant rooms of the larger starboard section?

Imagine what angle of list each could achieve as you cut through or removed the connecting fixings. Then there would be the issue of adjusting the trim to enable you to align and reconnect them together again once outside the lock gates in open sea.

Okay, so say the engineers could overcome all these technical issues and assume that the pontoon was connected securely and is in trim. The route to Portsmouth would take us down the Bristol Channel with its notorious tidal flows due to the fact that the Channel has the second highest rise and fall of tide in the World!