BLOCK-MACHINERY. To acquire a greater degree of accuracy and uniformity, as well as celerity, in the making of blocks, Mr Walter Taylor of Southampton took out a patent in the year 1781, to secure to himself the benefit of some improvement he had made in the construction of the sheaves; he also shaped the shells, cut the timber, &c. by machinery, which was put in motion by water on the river Itchin, near Southampton, where he carried on so extensive a manufactory of blocks, as to be able to contract with the commissioners of the navy for nearly the whole supply of blocks and blockmakers' wares required for the use of the royal navy.
Mr Dunsterville of Plymouth had also a set of machines for making the principal parts of blocks, which was wrought by horses; his manufacture, however, of this article was not carried to any great extent; but the blocks made by this machinery, as well as those by Mr Taylor's, were said to be of a superior quality to those constructed by the hand, though still deficient in many respects.
No objection, however, would probably have been made to the quality of the blocks furnished by Mr Taylor, and used in the navy. It would rather appear that the enormous quantity consumed in the course of a long protracted war first called the attention of the admiralty or navy board to the possibility of some reduction being made in the expense of so indispensable and important an article in the naval service; and that it was not prudent to depend entirely on a single contractor, whom accident or misfortune might disable from fulfilling his contract. A fire might destroy his wood-mills, in which case it would have been difficult to procure, in all England, an adequate supply of blocks for the navy.
On these considerations, it seems to have been the intention of government to introduce, among other improvements then carrying on in Portsmouth dock-yard, a set of machines for making blocks, at the new wood-mills erected in that yard in 1801. About this time the improvements which had been introduced into private concerns were gradually finding their way into the great public establishments of the country. Still, however, an old maxim seemed to prevail, that government ought not to be its own manufacturer. This maxim, though perhaps generally just in political economy, is, we conceive, neither just nor wise when applied to those articles which are of the first necessity in the king's navy. Indeed, where the safety of so many thousand lives depends wholly, as is sometimes the case, on the strength of materials and goodness of workmanship, it is most desirable that the whole ship, and every part of it, from the pin of a sheave to the sheet anchor, should be manufactured under the immediate superintendence of respectable officers in the king's service.
About this time, too, Mr Brunell, an ingenious mechanic from America, had completed a working model of certain machines for constructing, by an improved method, the shells and sheaves of blocks. This model was submitted to the inspection of the lords commissioners of the admiralty, and by them referred to General Bentham, the inspector-general of naval works, who represented that, as the making of blocks was one of the purposes for which a part of the force of the steam-engine erecting at the wood-mills was intended to be applied, he did not hesitate to recommend the new machine, as an invention which would enable the government to construct its own blocks with a greater degree of celerity and exactness than those which were then in use; and that it appeared to be well suited for manufacturing blocks of every description and size, with a degree of accuracy, uniformity, and cheapness, far beyond any of the methods hitherto practised. The adoption of Mr Brunell's machinery was the consequence of this opinion.
The advantages to be expected from blocks so made were stated by Mr Brunell to consist,—first, in bringing the shape of the outside of the shell to certain determined dimensions, so that those of the same size should actually be so, and not differ from one another, either in the proportion of the mortises, or in the shape and dimensions of the outside; secondly, in adding strength where it was wanted, by making the head and bottom more substantial, and less liable to split; and, thirdly, in leaving the wood between the two mortises thicker, so as to admit a sufficient bearing for the pins,—all of which would be accomplished without requiring any dexterity on the part of the workmen, but entirely by the operation of the machinery. The uniformity and exactness with which they were to be made would be attended with another important advantage to the public; the difficulty of counterfeiting them would act as a precaution against embezzlement. Another very considerable advantage would be derived from the employment of much waste wood in the dock-yard, usually sold for little or nothing, for firewood and other purposes.
The sheaves or shivers would, by this new machinery, be made so mathematically true, and so exact to each other in their thickness and diameters, that every sheave of any particular size would equally fit any shell of the size for which it was intended; and the inconvenience to which ordinary blocks are liable from the friction of the ropes against one or alternately both of the sides of the mortises, was intended to be removed by placing a sheet of metal on the upper part of the mortise, bent to the proper shape by an engine adapted for the purpose. Brunell also proposed a new form for the clue-line and clue-garnet blocks, so as to secure the sails from splitting, by preventing the points of the sails getting into the blocks; which has since been adopted and greatly approved of in the navy.
In the sheaves, instead of the double coat or cogue inserted in two halves, he substituted a mixed metal coat of a new and particular form, which will be described hereafter, of increased strength and durability. This coat was to be cast with precision in moulds, and fitted by an engine with the greatest nicety; and the pins or axes of the sheaves were to be of wrought iron, case-hardened and coated with tin, which would preserve the iron from rust in the parts which are not kept free from it by friction; as it has been found by experience that, however tight the pin be forced into the shells, the water will insinuate itself and corrode the pin; and when this is the case, the rust soon extends itself to the parts on which the sheave turns, and renders it unfit for use.
From the machines that were already completed for manufacturing blocks of certain dimensions, Mr Brunell