Volume Three - The Pontoon Era - The new pontoon or floating dock . . .

	One day later Swan Hunter produced a detailed estimate for manufacture of the dock and its installation at Penarth. A price of £39,900 was quoted on the 12th January to the Penarth company.
	A letter from The John Dry Steam Tugs Limited undertaking to tow the pontoon from the Tyne to Penarth using two tugs.

Obviously, once the pontoon was designed by Clark & Standfield in London and constructed at the yard of Messrs Swan, Hunter, & Wigham Richardson at their Wallsend-on-Tyne yard, it had to transported to Penarth and the best, the only, way to achieve this is by sea. A number of companies were contacted to provide quotations for the towing operation since the pontoon was a fixed installation at Penarth and did not require engines for moving her, just the means to lower and raise her in the water! The John Dry Steam Tugs Limited company were subsequently awarded the contract.

The dock at Penarth was constructed with lock gates 60 feet (18.3m) wide thus restricting the width of ship which could be repaired at the pontoon. The maximum width of vessel was therefore defined as 55 feet (16.8m) and ships at that time with that width were generally limited to approx. 380 feet (115.8m) in length with a draught of 18 feet (5.5m) and an overall deadweight of 4,200 tons.

To achieve this width, the pontoon had to be constructed wider than the maximum width of ship and a figure of 75' – 0½” (22.9m) was defined. But this width could not enter the dock so a number of possible technical solutions were proposed to overcome the problem.