key would open a pallet that would release the air up to the pipe ranks. Later designs, as technology progressed, started to encompass more of what could be found in church and other organs and more complex mechanisms, including rollerboards, pedalboards, reed organs (rather than pipes), and eventually electric rather than mechanical actions. Such residence organs were the province of professional house organ makers (who continue to exist even today) in the main, with a notable exception of Toggenburg where (at that time) residence organs were often constructed by amateurs and enthusiasts themselves. Several such purpose-built residence organs survive from centuries past, including Claudio Merulo's organ in the Conservatory of Music in Parma, and the residence organ of Marie Antoinette that is preserved at Versailles. For comparison, out of the 761 residence organs built by Aeolian between 1894 and 1932, only 65 survived to the end of the 20th century. (One such was the one at Longwood Gardens in Pennsylvania.) Residence organs rose to greater popularity in the 17th century, and by the 18th century much larger ones were being built, in England, Holland, and France. It was the end of the 19th century and the turn of the 20th that saw the advent of large and complex purpose-built residence organs in the private homes of those wealthy enough to afford such things, usually not played by the owners themselves but by professional organists whose services they would hire, for private concerts and the like. A four-manual organ was built in Blenheim Palace in 1891 by the Willis company, for example, and such things were symbols of ostentation and opulence on the parts of their owners. But things changed in the 20th century with the advent of new technologies. Right at the start of the century the paper-roll playing mechanisms of the pianola were incorporated into residence organs, which had the side-effect of eliminating the profession of residence organist, requiring the operator to do no more than operate the organ stops and expression pedals (which, in its turn, was eliminated within a decade, that too being encoded onto the paper roll itself). Residence organs in the 1930s grew to encompass an even wider range of instruments with the advent of the electronic organ and (later) the analogue synthesizer as home organs. There has been a "purist" backlash against these; and even today one can find companies that will build "real"