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

Mr. J .B. Redman cont'd :

The Authors stated, “ After the first starting of a slipway, slight settlements are sure to take place, but are easily compensated by wedging up the rail-bearers when required.” He thought that paragraph was very suggestive as to the increased difficulty there would be either in hauling up or in launching a vessel of 5,000 or 6,000 tons, like the “ City of Rome.” No doubt piling for such purposes was objectionable.

There had been an example, on a large scale, in the very great difficulties that occurred in the launching of the “ Great Eastern.” Notwithstanding all the calculations made with the greatest accuracy, and the care taken with the piling and the preparation of the bed for the broadside launching of that vessel, he believed it was generally acknowledged that it was the slight inequalities arising from the greater bearing power of the piles as compared with the intervening spaces, the very slight irregularity produced thereby, and the increased friction and resistance to the moving mass, that caused Mr. Brunel so much trouble, and possibly hastened the termination of his career.

The Authors had further stated, “ In a slipway on the Authors’ plan at Penarth, the length of 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 two hours.” He should be glad to know whether that was a hypothetical case, or whether such a vessel had actually been handled.

The Paper also stated — “Since the slipway was set at 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.” It would be interesting to know the tonnage of the largest vessel so handled.

The Authors had further stated, “ There is, unfortunately, little room for doubt that in many instances graving and other repairing docks have been a source of considerable loss.” Undoubtedly they were a source of loss when they were dry docks or graving docks only by courtesy, and leaked exceedingly.