This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1882 edition. Excerpt: ...place his foot, while he removes the front shades in order to reach the pipes planted accordingly. In the swell-boxes of church organs the sides of the box are generally fitted as Fig. 50. doors; then, the pipes being planted with the tallest in the centre, diminishing in height to each end, half of them can be tuned at one operation. When the pipes are thus planted, the top of. the box will slope towards each side from a central ridge, like the roof of a house. We cannot doubt that many of our readers have had, or may have, opportunities of examining the construction of the shutters or shades of a swellbox. We have sketched it, however, in Fig. 50. The shades are 6 inches in breadth, and of the same thickness as the rest of the box, and each shade turns on pins let into the ends of it at a distance of 2 inches from its upper edge. These pins work in notches cut in the cheeks of the box, so formed that any shade may be easily lifted out and replaced. The edges of the shades are bevelled to half a right angle so that they overlap when closed, and the bevelled surfaces are faced with leather or cloth to 11 r---f shut in the sound more effectually. The mode of opening the shades, and 11 H ft so producing a crescendo, is shown in Fig. 51. a, 6, c are arms of oak, morticed into the shades at the level of the pins, viz. 2 inches from the upper line; d e is a long rod or tringle of wood, connecting all these arms by pins passing through them and itself. It is evident that by drawing up this rod at its top, or by pushing it up from below, we shall open all the shades at once, and as they are hung on axes e Y placed at one-third of their breadth, they F,g"5I" will close by their own weight when released. The leverage by which this...
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