Volume Ten - Pre-Victorian to the present day - even more aspects - The Patent for the Penarth Slipway - 1881 . . .

In a slipway on the Authors' plan at Penarth, the length of the ways is 867 feet, and the expense of placing and hauling up a vessel weighing 2,300 tons may be taken as the wages of sixteen men for one hour and three men for tow hours, while in Morton's system, in which the links had to be disconnected, at least another hour and a half would be taken in hauling up, and the labour of twenty men would be required during the whole operation, lasting four and a half hours.

The engine power at Penarth is about 40 indicated HP., the water being supplied from the hydraulic pumping engine at the adjacent docks. Since the slipway was set to work in 1879 no less than one hundred and thirty ships have been hauled up and repaired, without the slightest accident, beyond the breakage of a few rollers at first starting.

Whatever form of hauling gear be adopted, it will generally be of advantage to have a supplementary engine and crab, with chain for traversing the empty cradle quickly up and down, especially in positions where there is likely to be an accumulation of mud at the lower end of the ways, in which the empty cradle when run down would not acquire enough velocity to overcome and remove the obstruction.

This Paper would be incomplete without some statement as to the cost of constructing such works as have been described ; but the Authors have much difficulty in giving any general estimate which is not likely to be misleading. In may, however, suffice to state that a slipway such as that shown in Plate 5, Figs. 1 and 2, . . . .

◊ Slipways for Repairing Ships - Plate 5 - Figs. 1 and 2.

. . . could be constructed for about £25,000 (equivalent to circa £2,975,000 in 2018), including the foundations, 850 feet of ways, cradle, and appurtenances, hauling machinery with links, and one timber side jetty, but exclusive of land.