Dom Bedos, The Organ-Builder, Transl. by Charles Ferguson, Raleigh: Sunbury Press, 1977. Chapter III. Section one. Building manual keyboards. [Annotations by Birkett in square brakets] 700. Bone is preferable [to ebony] for organ manuals [i.e. non-pedal keyboards] because it is harder and thus lasts longer. Leg bones of oxen are use, being sawn into strips as wide as the keys. In Paris, these strips may be bought for three sous apiece, but in the provinces, unless they can be sent from Paris, they must be made. They are roughed out with saw and rasp. Before finishing they are bleached as follows. 701. In a skillet, slake a lump of quicklime the size of a fist. When the lime is slaked and reduced to a paste, add about 2 pintes (3 or 4 livres) of water, and a bit of powdered alum. When all are well mixed, put the bone in and place the skillet on the fire. After it has boiled for two or three minutes at most, remove from the fire; when the water has cooled somewhat, skim it gently and thoroughly. Let the contents cool, then remove the bone and wash it with fresh water. Let it cool slowly; if it dry too rapidly, in a warm place or in the sun, it will crack. Note also that if the bone be boiled longer than I have indicated, it will burn or char, and be spoiled. 702. When the bone is thoroughly dry, it must be finished. One side is dressed with a serrated plane [i.e. a plane blade that has grooves, as is also useful for planing wild-grain veneers; bone is very hard on tool edges too]. The caps are dressed to the exact width of the keys [which means the joins line up with the edges of the keys that have already been laid out on the panel, so that the joins disappear when the keys are cut]. Both ends are squared, and the caps are pressed into a wooden jig which holds them while they are planed first with the serrated plane [on one side], then with the ordinary plane [on the other side, the one destined to be played]. The jig enables the workman to make the caps uniform in thickness. When finished, they are glued in place on the panel, with the roughened side down [to allow somewhere for the excess glue to go, no different from all wood-working involving hide glue]. They are covered first with paper, then with a folded rag. Then a bar or beam is laid on, as thick as the caps are long, and the work is clamped with two or three holdfasts. When the glue is quite dry, the caps are planed with a straight plane or an ordinary plane with the iron reversed, and they are carefully smoothed. [All this occurs before the key panel has been cut apart to form the keys. Some builders, e.g. the Ruckers, cut their keys before covereing with standard size bone slips.] Stephen Stephen Birkett Fortepianos Authentic Reproductions of 18th and 19th Century Pianos 464 Winchester Drive Waterloo, Ontario Canada N2T 1K5 tel: 519-885-2228 mailto: sbirkett@real.uwaterloo.ca
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