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but as they increase in age, so do they, in consequence of progressive warping, require it the oftener.
The constant tension of the strings effects such a strain upon the piano, that the opposite corners (in the direction of the wires) of almost every one, however new, will be found, if ‘accurately examined, to be turned up more or less. Thus it will be easy to conceive, that so long as the bed retains inflexibly its straight or level form, the piano will last, possessing the property of remaining longer in tune, and of being more easily tuned: but let the strings once gain an ascendancy over the horizontal level of the bed, and the turning up thereof will proceed with accelerated speed.
In Calcutta, where people enjoy the means, and have the opportunity, they do not keep their pianos beyond a year, but pay for an annual exchange ; thus getting rid of them before the warping gives annoyance, and is not so great as to render them unsaleable; but it is not so with people situated away from the metropolis, who are compelled to take whatever pianos are sent them, which they are doomed to use for years, until they may be seen with two inches and even more, turn up: in this state many are quite unconscious of the defects of their pianos, and attribute their-not remaining in tune to climate, to want of skill in the tuner, or to any other cause, rather than to the deplorable state of the instrument.
To prevent this warping, several plans (and patents I believe) have been adopted by makers. Some of them consist in the application, in various ways, of plates and bars inserted at the back, and in the inside of the piano. One of the plans adopted is, that of a square iron bar, about three and a half feet in length, and upwards of l5 lbs. in weight, screwed (in the direction of the wires) to the underside of the piano, with five wood-screws, scarcely weighing three drachms each, and a slight bolt, to connect the end of the bar, by means of a nut and screw to the end of the piano; indeed, if this bar were even more substantially fixed to the instrument, it does not appear to me calculated to be of any material service in strengthening it.
In January, 1833, Itook to pieces an old piano belonging to a friend, with the intention of trying to straighten it. During this operation, whilst reflecting on the immense pull that the wires constantly exert beyond all power of the bed, as at present constructed, of any piano to resist; it occurred to me, that if a counter strain to the wires above could be contrived and attached to the opposite or underside of the bed, the desired object of keeping the piano straight, thereby rendering it far more durable, and disposed to keep longer in tune, would be accomplished.
The compensation for the strain of the wires above is effected by placing iron rods (two or three) in a direction parallel with the strings, but below the bed of the instrument. The rods are fixed at their extremities by a joint, to iron clamps, which are screwed to the underside of the bed, and bolted at one end of the piano, through the bed and block that holds the tuning pegs, and at the other, through the bed, block,» and plank. The extremities of the rods being thus fixed, their power is obtained by drawing them over a stout wooden bridge, placed at about two feet from the end, just below the keys of the highest notes, and then drawn by adjusting frame, nuts, and screws, as tight as is necessary ; as will, I hope, he distinctly shewn by the accompanying plate and description.
Fig. I, is an elevation ofa piano, which shews one of the rods, A, as applied below, drawn by the adjusting screw C tight over the bridge B. (The same letters apply to all the figures.) The bridge B is shewn on a larger scale at fig. 3. By the drawing, fig. l, the end of the bridge B seems to present an unsightly appearance, but it is not so in reality; the rods crossing the bridge, at some distance from the front, as at Iin figs. 2 and 3; and so little are they visible, that they would not be observed, unless attention was drawn towards them.
The frame or adjusting nut C turns at one end on a knob or head, formed on the end of the (short) rod, having a flat brass ring interposed (to reduce the friction) between its head and the inside bearing of the frame : the other end of the frame is made thick, as at figures 6 and 7, having a screw formed within it, to receive that on the end of the rod. The screws are raised above the surface, and not cut into the thickness of the rods.
Fig. 2, represents the piano, turned upside down. A A A are the rods, running in the same direction with the strings of the piano, intended to be expressed by the shaded part between D D D.
E E E, clamps with joints b, figs. 4 and 5, to receive the ends of the rods, in which they are held by a small bolt. The clamps are sunk in the wood, as shewn by the dotted line 0 c, are broader towards their outer ends, 11 d, and thicker towards e e, that they may oppose more surface in the wood, against the tension or drag of the rods A.-F. figs. 2 and 6, is a clamp of another description, (it was applied to one of the pianos operated upon ;) by it the bolts fixing the ends of the three rods are connected: the two outer bolts GG, passing through the end plank of the piano, and the centre one, H, through the bed, block, and metal plate, on which the wires are fixed ; instead of this connecting the ends of the rods by one clamp, separate clamps
like EE, figs. 4- and 5 have been used: the clamps EEE, besides being bolted through the piano, are each further secured by two wood screws.
The exact spots for fixing the clamp at both extremities of the
rods, must be determined, according to circumstances, by the judgment of the individual applying them, because pianos vary in their internal construction; on which account also, it is obvious, that they would be applied, with the greatest advantage, by manufacturers in the first construction of the instruments, as the makers would have it in their power to accommodate the internal arrangement of the pianos to the most desirable position for fixing them. . The rods should he applied to new pianos, before warping takes place; they may be put to old instruments, though not with equal advantage, from the circumstance of the blocks of wood placed at the end, under the sounding board, together with the iron bar, which is screwed at one end on to the block, bearing the tuning pegs, fixed at the other to the metal plate, on which the strings are hooked, being thrust, by the warping of the instrument, out of their places; for when a piano has been straightened, they will be found to have parted from those original bearings, on which mainly depended the strength of the piano. However objectionable this loss of bearing may be, the power of the rods is nevertheless the more clearly indicated by their sustaining the piano in its straightened state against the tension of the strings.
Fig. 3, B, is the bridge; ff are holes cut obliquely through it, to lighten it; ggg are the places where the rods cross it; the bridge is 2%; inches thick, and with the plank h h above it, in depth 3% or 3% inches; the dotted lines at I and Li shew the body of the piano. across its breadth.
Fig 5, K, is the bolt that fixes the clamp E, by passing through the block, (bearing the tuning pegs.) the bed of the piano, and by a nut and screw fastening below the clamp. The whole of fig. 5, is represented upside down.
The rods are of round iron wire, 13,, of an inch in diameter. Hitherto, not less than three rods have been put to a piano; but perhaps two might be found sufficient. It is possible to draw the rods too tight, especially when first put on, and if the piano was much warped; for the instrument does not accommodate itself to the new tension for some time : it will therefore be necessary, until it settles, to examine it daily; for if the rods are not slackened by turning the adjusting screws, the strings might be endangered.
Many pianos may be seen with the end plank M. figs. 1 and 2, split; occasioned entirely by the pull of the strings. The bolts GG. figs. 2 and 6, secure the plank against this failure. The block