ORGAN, an instrument of music. The word is Greek, lyavor, which signifies instrument or any kind, and is very appropriately given, by way of eminence, to this incomparably the grandest among musical inntrumcnts.
In the short abstract of the history of the art, given under the word Music, we have noticed (Art. 27.) the important effects which the invention of this instrument, and its introduction into the church service, gradually produced on the science or art ; and that it was probably an improvement on the HYDRAULIC ORGAN of the an cicnts.
Of this ancicnt instrument, so little is known, not withstanding the long description of it given by Vitru vius, and the labours of learned men to explain that description, that we shall bc content with quoting what Dr. Burney says of it in the short account he has given of ancient instruments of music, at the end of the first volume of his HISTORY.
" The last wind instrument of which I shall speak, is the Hydraulicon or water-organ, that was played, or at least blown, by a cataract or fall of water. Indeed, it has been much disputed, whether it was played by fin gers, by means of levers, or keys; and yet the descrip tion of it by Claudian seems such as would suit a modern organ, only blown by water inosead of bellows.
" In Athenmus, lib. iv. p. 174, there is a history and description of this instrument. Ile tells us that it was invented in the time of the second Ptolemy Euergetes, by Ctesibius, a native of Alexandria, and hy profession a barber; or rather, it was improved by him ; for Plato furnished the first idea of the hydraulic organ, by invent ing a night clock, which, according to Perrault, Vitruv. lib. 10. was a clepsydra, or water clock, which played upon flutes the hours of the night, at a time when they could not be seen on the index.
" This musical clock must have been wholly played on by mechanism. But neither the description of the hydraulic organ in Vitruvius, nor the conjectures uf his innumerable commentators, have put it in the power of the moderns either to imitate, or perfectly to conceive the manner of its construction ; and it still remains a doubt, whether it was ever worthy of the praises which the poets have bestowed upon it, or superior to the wretched remains of the invention still to be seen in the grottos of the vineyards near the city of Rome.
" In the collection of antiquities bequeathed by Chris tina, Queen of Sweden, to the Vatican, there is a large and beautiful medallion of Valentinian, on the reverse of which is represented an hydraulic organ, with two men, one on the light, and one on the left, who seem to pump the water which plays it, and to listen to its sounds. It has only eight pipes, placed on a round pedestal ; and as no keys or pet formers appear, it is probable that it was played on by mechanism." 'fhe pneumatic organ, as the modern instrument blown by bellows has been called, in contradistinction to the hydraulic one, is a very complicated and ingenious piece of mechanism. Although it is spoken of as one instrument, yct, strictly speaking, it is a collection of many instruments, all brought under the finger of one pet former, and so ingeniously contrived, that he has it in his power to play on any one singly, or to combine seve ral, or all, according to his taste, in order to produce variety of effect. we suppose an instrument having a set of pipes, giving the twelve notcs of the chromatic scale, corresponding to cach octave in the key-bocrd of keyed instruments, described under NIosre, Art.80-87, Ive have the idea of the simplest organ ; and such an instrument, provided its key•board were as extensive, would he as complete, as far ns regards the scale, as the piano-forte. But organs have many sets uf pipes, or sTors, as they arc called, of very different qualities, to the sante key-board, and frequently several key-boards, each baying many stops belonging to it ; insomuch, that the grandeur and variety of effect which it puts in the power of an able organist to produce, is almost endless. Of the mechanism by which this is effected, we are now to give as minute an account as our limits permit ; and we shall begin by describing the pipes, the grand assem blage of which constitutes the ORGAN.