Some of our readers may be able to indulge in the luxury of a second pedal stop. This should be a Violoncello in metal, of 8-feet tone and length. In this case the pedal chest or chests will be regular sound-boards, with sliders; or the Sub-bass may be on a chest as already described, while the Violoncello may be on another, with two actions.
We have only to add, that the power and effectiveness of small organs may be increased by the contrivance called a "Terzo Mano" (Third Hand), or octave coupler. Let us suppose that an ordinary action has been fitted with backfalls in the usual positions. Then a second bridge, rising and falling by a draw-stop, is introduced, carrying skew backfalls which act on the pull-downs an octave higher than the first set. Thus the key CC will take down the Tenor C note, and so on throughout the scale. It is evident that the effect on the ear will be nearly, though not quite, the same as if each 8-feet stop had its corresponding 4-feet stop drawn with it. An Open Diapason will sound like an Open Diapason and Principal; a Stopped Diapason, like a Stopped Diapason and Stopped Flute, &c. To render the illusion complete, the pipes should be carried up twelve notes higher than the apparent compass of the key-board, that is to say, if the key-board has fifty-four notes the sound-board should have sixty-six grooves.
In a similar way the pedal Sub-bass may be made to play in octaves, producing the effect of a Sub-bass, 16-feet tone, with a Flute-bass of 8-feet tone added to it.
Of all such mechanical devices it must be said, finally, that neatness, accuracy, and noiseless precision of action are the conditions necessary to complete success.
OUR labours have hitherto been exclusively directed towards the production, in private workshops and by young workmen, of small organs adapted for domestic use. That such organs should be of varied character, and that they should represent the differing musical tastes and unequal mechanical ingenuity and adroitness of their unprofessional or self-taught constructors, is the legitimate outcome of the circumstances assumed.
The case of organs for churches must be regarded from a different stand-point. Designed for public use, and consecrated to lofty purposes, they should reflect no private fancies or peculiar tastes; should admit of no experiments or eccentricities; should be distinguished by excellence of material, finished perfection of workmanship, and solid stability of structure. We cannot, therefore, recommend the construction of any church-organ in a private workshop. The aim and object of this volume would be entirely misconceived by any reader who should imagine that we encourage such an ambitious attempt. However humble as to style of architecture the church may be, however unpretending the scheme for the organ may be, we must strenuously advocate the placing the order for its erection in the hands of a well-established firm of professional builders.