Page:Proceedings of the Royal Society of London Vol 4.djvu/289

Rh slaves off the coast of Africa, and had nearly fallen a victim, in common with the greatest part of his crew, to that pestilential cli- mate.

Sir Robert Seppings received his education as a shipwright under the late Sir John Henslow, Surveyor of the Navy, and continued in connexion with the important service of our dock-yards during a period of fifty years. He was the author of many important im- provements in our naval architecture, including his system of dia- gonal bracing and trussing, which formed the subject of two memo- rable Papers in our Transactions in the years 1814?* and 1818 f, and which attracted an unusual amount of public attention. The great principle of this method was such an arrangement of the principal timbers as would oppose a powerful mechanical action to every change of position of the ribs and other timbers in every part of the ship ; thus firmly compacting together the entire fabric^ and preventing that perpetual racking of beams and working of joints, which, in the ancient system of ship-building, produced hogging, creaking, leakage, and rapid decay ; and filling up likewise every vacuity between the timbers, which were occasionally the unavoid- able receptacles for foul air, filth, vermin, and various other sources of rottenness and disease.

These important improvements, though opposed to the inveterate - prejudices of the older shipwrights, a body of men who have not sufficiently valued and understood, in this country at least, the just principles of mechanical action, in the practical operation of ship- building, were universally adopted in the Navy under the enlight- ened administration of Mr. Charles York, and the powerful advo- cacy of Sir John Barrow :j: : and the merit of their author was ac- knowledged by his appointment as Surveyor of the Navy, and by the award of the Copley Medal of this Society.

This was not the only important improvement which Sir Robert Seppings introduced into our system of naval architecture. The Admiralty presented him with £1000 as a reward for his simple yet most useful invention of an improved block for supporting ves- sels, by which their keels and lower timbers were much more easily and promptly examined and repaired. His plan for lifting masts out of the steps, which superseded the employment of sheer hulks for that purpose, has been the means of saving much expense and labour. His new mode of framing ships has led to a much more ex- tensive use of short and small timbers, which were formerly of little value ; but the most valuable of all the reforms of construction for which the Navy of England is indebted to him, was the substitution of round for flat sterns, which afford increased strength to the frame- work of the ship, greater protection against pooping in heavy seas,

On a New Principle of Constructing His Majesty's Ships of War. —Phil. Trans. 1814, p. 28.

On the great strength given to Ships of ^War by the application of Diagonal Braces. — Phil. Trans. 1818, p. 1.

In very able articles in the 24th and 43rd Numbers of the Quarterly Review.