214 On the Euharmonic Organ. 



seen among the hearers of Mr. Liston's Organ, will favour the 

 Readers of your work, with their free and ingenuous opinions and 

 remarks, on it- merits and its defects, if any such they discover, 

 since the Philosophical Magazine has long stood distinguished 

 amongst its cotemporaries, for its correct and luminous exposi- 

 tions, of the mathematical principles of Music, and none will 

 be thereby more gratified, than, sir. 



Your very humble servant, 



Philo-Musicus» 

 The ))aper above mentioned is as follows ; viz. 

 " To the Musical Profkssors and Amateurs, who may attend 

 to try or hear Mr. Liston's Patent large, Enharmonic Or- 

 gan, with compound Stops, exhibiting at Messrs. Flight 

 and Robsdn's Room, in St. DIartin's Lane, LSI/. 

 " Mr. Fabey Se?i. with the view of aiding the perfect con- 

 ception and knowledge of the grand improvement made by his 

 friend Mr. Listen, begs tiuis to offer a few numerical facts, and 

 particulars, entirely divested of the muthematicul form in which 

 they have been derived bv him* and demonstrated, as to the 

 true values of the several Intervals on Mr. Liston's curious and 

 important Instrument. 



" There are in the Scale of 39 Notes on this Instrument, two 

 exceedingly small, and yet highly important Intervals (called 

 Schismas), between Cb and B', and between C and B'*, which 

 ])rove to i)e the Units of the Scale ; in terms of vvliich, every 

 possible Interval on this Intrumont, or even on one of a far more 

 extended 8ca!e, can be arithmetically expressed and compared, 

 with the utmost ease and accuracy, by every Musician who is 

 ready at addition and subtraction; (jualifications, in which it 

 would be a libel on the Readers of this, to suppose them wanting. 

 " The major Comma is 11, the major Semiln?ie is 57, the 

 minor Tone is 9«3, the major Tone is 104, the major Third is 

 197, the major Fifth is 35S, and the Octave is 612, of these 

 Schisma Units, respectively. 



" The tuning of this Organ, has been wholly conducted by 

 help of the three last mentioned concords, the Third, Fijth, and 

 Octave, each tuned q7iite perfect [whhout even tiie slowest Beats, 

 which it was possible to detect), and according to tlie process 

 which is described in the first 7 and in the 44th and 45th pages 

 of Mr. Liston's *' Essay on perfect Intonation" (which is on 

 Sale at the Music Shops), or in p. 421 of Phil. Mag. vol. xxxix. 

 Now following this process arithmetically, double 358 for the 

 two Fifths CG, Gd, tuned upwards from C, and deduct 612, for 



* " In a Series of Letters in the Philosopfiical Magazine, commencing in 

 its 28tli Volume in 1807, and since cjf'tcn continued : in the articles of the 

 ESmburg/i Eruyclojttvdia ; in the Monl Idj/ nnd Gentleman's Magazines, Ike. 



the 



