Thinking out of the box
When Abraham Jordan, (father and son), distillers by trade, announced, somewhere about 1700, that they were setting up business as organ-builders, critics pointed out that there is little connection between a pipe* of wine and an organ pipe. (*A pipe is a liquid measure of 105 gallons. )
Despite widely predicted disaster, the new enterprise flourished. In 1712, a press advertisement stated that the Jordans had built a “very large organ in St Magnus’ church, London Bridge …… consisting of four sets of keys, one of which is adapted to the art of swelling the notes, which never was in any organ before”. Thus was announced the coming of the swell division; this first contained 8 stops with a compass of 32 notes. The case (picture 1) remains.
Jordan built on the work of others: two possible influences can be traced. Short-compass echo divisions, placed in permanently closed boxes had been in use for many years; pieces using echo effects may be found in many collections of 18th century organ music.
The second influence may have been the sash "windows" provided in some organs to protect the pipes when instruments were not in use. A picture showing this arrangement in Father Smith’s organ at St Paul's cathedral is to be seen in Nicholas Plumley's book on Organs of the City of London (Positive Press ISBN 0-906894 06 9). These were a variation of the large, painted shutters used in a number of European organs for both practical and symbolic reasons.
Jordan’s swell added a pedal-operated sash to the echo box. (The cliché about “thinking out of the box” would undoubtedly have been applied if it had been known at the time; despite primitive dentistry, life in the 18th century had its advantages!) The considerable weight of the single shutter, despite slatted construction, made smooth operation difficult, often with audible bangs at the limits of travel. To keep shutter size manageable, the compass of swell divisions was limited, with tenor C (or even fiddle G) as the lowest note. This restriction remained for over half a century, until Samuel Green substituted shutters on the model of a Venetian blind. His used horizontal shutters are still widely used (picture 2). In a "Venetian swell", total extent of shutter travel is much less - allowing for greater leverage at the pedal and consequentially less physical effort. Furthermore, a degree of counterbalancing could be introduced into the design. Full compass swell divisions to CC became practicable (though for many years these were far from universal).
Swell boxes tend to be directional in effect. That in picture 2 throws sound forward and downward. In picture 3, the shutters open upward, projecting the sound of an echo division toward the ceiling and increasing the ethereal effect.
Control of the swell has always been something of a problem. The original “trigger and stick” swell pedal exists in many older organs and, unfortunately, has been employed in some of recent date. Its deleterious effect on pedalling technique (as well as discomfort caused by its prolonged use) was recognised but a practical alternative was slow in coming. One proposal was for a mouthpiece - like that of a cigar-holder - to be fitted to a flexible rubber tube, connected to the swell mechanism in such a way that blowing opened the box and sucking closed it. Not surprisingly, this unhygienic arrangement found no favour. (If the state of technology had allowed, an arrangement similar to that suggested here might have been adopted.)
Balanced, centrally placed pedals that may be operated by either foot came into use about 1900 and have become standard on most instruments built since that date. One centrally placed seat back exists - lean forward to open, backward to close the box. This is at Rock church, Northumberland, England and is seen in picture 4. Hence the “safety belt”, worn by Scott Farrell, organist of Newcastle Cathedral.
Footnote: Spanish builders may have anticipated the Jordans by enclosing single solo stops in a form of swell-box.