On the title page of the 1819 publication appears the statement to which Griepenkerl refers in his extended essay Bemerkungen as established evidence for the claims of authenticity of all contained in the pages of this publication.
New edition with directions for its true interpretation, these having been transmitted from J. S. Bach to W. Friedemann Bach, from them to Forkel and from Forkel to his students. 
The claim of direct descent from Johann Sebastian is here stretched through several generations. We know for certain that the composition was composed before 1730; music manuscript P421, in an unidentified hand but long regarded as one of the most reliable manuscripts of this work, contains the dating 1730 on its cover.  The 1819 edition was edited by Griepenkerl nearly 100 years after its composition. Griepenkerl's changes in notetext and lavish performance indications are nonexistent in any reliable manuscript. At this point the need to ask questions about authenticity in general, and Griepenkerl's statements in particular, becomes urgent.
Did Forkel, who died one year before the 1819 publication, see and approve Griepenkerl's editing? Possibly, but we do not know. In his BemerkungenGriepenkerl claims that his "overladen" directions are the result of direct inheritance from Sebastian himself through his son, through Forkel and his students.
The 1819 claim of descent from J. S. Bach himself through his own son and thence to Forkel and Forkel's students placed Griepenkerl as the holder of the holy grail - the oracle who possessed the original notetext, thought and performance practice of J. S. Bach and the agent for direct transmission from the original source. With Forkel we perceive the early manifestations of modern concern with authenticity of manuscripts and notetext. Forkel's biography of J.S.Bach, his position as manuscript collector and his association with Bach's sons further, and not unreasonably, solidified his position as the prime representative of the sources of Sebastian's original manuscripts and performance practices. The notetext of Griepenkerl's edition of the Chromatic Fantasia and Fugue was related to the 1802 publication that was overseen by Forkel and for which Forkel provided a manuscript. But the 1819 edition of Griepenkerl/Forkel did not recognise the underlying power contained in the flow of creative concepts, forms, structures, performance media and practices which had gushed forth since 1750 and had continued to develop in new directions, being strongly established by 1819. The luxurious notetext alterations and stylistic addenda in the music text documents this point.
Griepenkerl, who was born as late as 1782, grew up in the heated atmosphere of the continuously developing romantic movement with its expanding orchestral sonorities and the conceptual aura radiating from the power of the era of Enlightenment. The piano was already well-established in the late eighteenth century as the prime solo keyboard concert instrument, with John Nepomuk Hummel and Carl Maria von Weber leading in this direction. By 1819, the aesthetic orientation of Forkel and Griepenkerl could not escape the influence of the profoundly different sense of form and structure, the new instruments, sonorities, orchestral and solo techniques that had evolved since 1750, leading to such different styles and products from those that formed and influenced Sebastian, as well as the inevitable transitions and metamorphoses that invaded these in manners of performance. The organisations of form such as the piano sonatas and chamber music of Mozart and Haydn, the operas of Mozart, the concept of Sonata-Allegro form in Beethoven, and the overall structural departures throughout their solo works, concerti, operas, symphonies, etc., from Bach's chief structural concepts nurtured equally evolving performance practices. Moreover, playing for a continually expanding secular public becomes enmeshed with influences not present in the performance manner that is rooted in the needs and the aura of church or court, where most of Sebastian's music was performed. By 1819 the pianoforte, having attained the prime position as keyboard instrument for concert and home, had long displaced the harpsichord and clavichord as had, also, the main body of keyboard repertoire which consisted chiefly of compositions for piano.
Along with Griepenkerl's claim on the title page of direct overall transmission from Johann Sebastian himself of the authentic presentation of the notetext and performance instructions is the unconditional instrumental allocation on the title page for performance: "Für das Pianoforte".  If we are to adhere to the claim of Griepenkerl that this edition represents Sebastian's intentions, then, are we to believe that Johann Sebastian specifically allocated the piano as the instrument for the performance of the Chromatic Fantasia and Fugue? Can this be an authentic, an original instrumental allocation, made prior to 1730 by Sebastian? Even before opening the first page of Griepenkerl's edition one sees two printed statements on the title page that are seriously questionable. My grounds for questioning are related to both the past and future-facing directions of Janus.
Until 1967, the piano was regarded as being outside Bach's interest or usage and was placed under a blanket taboo by the protagonists of the 'authentic' movement. The harpsichord was hailed, besides the eighteenth century organ, as the correct, authentic keyboard instrument for Bach's keyboard works. The clavichord, also a standard instrument of Bach's time, was afforded a slight nod but, more often than otherwise, was largely neglected or ignored, due mainly to its weak volume, so impractical for modern recital conditions in public halls. Moreover, the clavichord's tone qualities and performance technique contradicted the approved stylistic approach attributed to the harpsichord's plucked action and crisp, 'clean' tone. The clavichord's singing tone and its capacity for crescendo/diminuendo achieved by the required technical device of a physically applied and controlled vibrato is in opposition to all the nineteenth and twentieth century commandments for clarity, crispness, non-legato, 'clean' performance, devoid of volume gradations. Although the clavichord became the favourite of Carl Philipp and others in the mid-late eighteenth century, due to its capacity for expressiveness so central to this period of Empfindsamkeit, it never fulfilled their ambition to succeed as a concert instrument, due to a large extent to its limited volume. Moreover, the flowering of interest in expanded levels of volume and timbre was influencing creative musicians in the direction of the capabilities and characteristics of the surging developments of the pianoforte.
The twentieth century taboo of the piano and its stylised manner of pianism in the late nineteenth and early twentieth centuries made great sense. Useful as were the continuous expansions of the piano's sonority and its potential for varied figurative structuring and technical display, these, idiomatically, are manifestly inapplicable to earlier senses of form and sonority. The piano itself was subjected to total exile from performance of music pre-dating the mid-late eighteenth century. But new data and its accompanying new perspectives have led to fresh considerations of the piano per se.
In 1967, the Polish music magazine Muzyka published incontrovertible evidence that Johann Sebastian was, in his later life, a salesman for the Silbermann piano. This spectacular discovery - spectacular in the sense of the long banishment of the piano - was the surfacing in Poland of a receipt for the sale of a Gottfried Silbermann piano to a Count Branitzky, dated May 9, 1749. The receipt was signed, unmistakably, in the hand of Johann Sebastian. In the early 1970s one of the most eminent of present-day scholars, Christoph Wolff, wrote an article in the Musical Quarterly on Bach's Musical Offering, in which this information was conveyed to the English speaking world for the first time and a copy of the receipt was reproduced.  Surprising as it may seem, this news has still not reached many professional musicians and an even greater section of the musical public.
As a result of this discovery, a sharp crack in the wall that separates Sebastian from the piano resounded throughout the academic world. Since the discovery of Bach's active association with this instrument the performance of Sebastian's keyboard music on the piano has received increasing acceptance by the musicological community, which has been the arbiter of correctness for over 150 years. But the security of a long-held faith still anchors a general defensiveness. On the other side of the coin that carried the insignia of taboo, the recent surge of relativism and post-modernism asserts a kind of unconditional allowance of legitimacy of every individual's choice of instrument and performance manner. These fashions, along with the subject of the piano, its evolution, the influences that evolved in its continuous manufacture throughout the nineteenth and twentieth centuries, as well as its contemporary usages by composers and performers merits a long chapter that is outside the scope of the essay.
Griepenkerl's authority, both as the leading editor of the Griepenkerl, Czerny editions of Bach's keyboard works, published by Peters (with Roitzsch added later) throughout the entire nineteenth century and well into the late twentieth century, and his editorship of organ works with his copious annotations, was supported in the case of BVW 903 by his close association with Forkel. In c. 1839 Peters added Czerny's name to Griepenkerl's edition. Czerny's role in the Chromatic Fantasia and Fugue was that of adding fingering indications. My comparative study of notetext and performance indications of the first edited publication of 1819 and the first 'Czerny' c. 1839 edition revealed no contributions or alterations of notetext or performance indications by Czerny to Griepenkerl's editing. Although Czerny's contribution is limited to fingering, his name having become illustrious in the field of piano playing methods and technical studies, as well as the general distinction he enjoyed as a pupil of Beethoven, Griepenkerl's edition became known as the 'Czerny' edition; it is still mistakenly identified as such, even throughout our century.
That Griepenkerl's edition of the Chromatic Fantasia and Fugue carried the insignia of authority throughout the nineteenth century is demonstrated by the fact that Clara Schumann, probably the greatest and most influential pianist of that entire epoch apart from Liszt, owned this edition. As is universally known, Clara Schumann was also a teacher of many students throughout her long life. No doubt she performed and taught according to the notetext and performance indications of this publication for her copy contains several fingering notations regarded as hers.  Her tradition was passed on well into the twentieth century. I myself met a student of Clara Schumann, Lady Noble of Bath, England, who was ninety years old at the time that I performed, about the late 1950s/early 1960s, at a music festival in Bath, UK. At the age of fourteen, Lady Noble had studied with Clara. Proudly displayed framed and hanging on the wall of the entrance hall of her home in the Royal Crescent in Bath, was a late photograph of Clara that she had given to her. As late as 1951, Kodaly based his arrangement of the Chromatic Fantasia for Viola on the notetext of the 1819 edition of Griepenkerl.  Clearly, the ring of Griepenkerl's authority had still continued to sound strongly, in some quarters, long after his death in 1849.
Despite Griepenkerl's eminent position and his patent influence on musical thought and practice, younger generations with fresh views arising in the latter years of Griepenkerl's lifetime were re-thinking the conventional dogmas implanted by their musical ancestors. One of the earliest, possibly the first, of all public exchanges regarding authenticity in Bach performance instituted by major figures in the music world appeared in 1848 when Adolf Bernard Marx (1795-1866) published his views on the subject and was promptly challenged in a return letter by Griepenkerl. Marx, a strongly influential mentor for some years of Mendelssohn, became, and continued to be after his break with Mendelssohn, one of the most highly respected musicians of his time. Although this public correspondence is not unknown, its important implications have received little attention. An incisive articulation is here expressed of the two opposing views which have prevailed since that time, and which today is more often than not regarded as a twentieth-century development. The two-sided controversy, established so clearly here, is launched on a long career. The opposing positions and the authority of each writer in this exchange are so seminal that they form a prototype of the two views that have split the Bach camp for 150 years. That which should have been a communal trysting place magnetised by mutual interest, Marx's expressed hope, was partitioned off into a theatre of war.
A letter, published in the Allgemeine Musikalische Zeitung of 19 January 1848, entitled "Sebastian Bach's Chromatische Fantasie: A Few Remarks by A. B. Marx" sparked off the exchange.  An abbreviated scan of a few major points expressed in their letters sets the scene for the sustained development of these positions in the succeeding years.
Marx's opening remarks contain a clear allusion to Griepenkerl's claims of authenticity and his performance instructions in his 1819 edition as deriving directly from Sebastian and pupils. "It is said that Bach passed on to his pupils, and they on to us..."  He continues with a general challenge. He disagrees with the romanticists who regarded Sebastian as out of date, referring to him as "the wig", and he decries, also, the overblown performance style of the universally-admired virtuoso Franz Liszt.
In describing a performance that he heard by Liszt, of Bach's Chromatic Fantasia and Fugue BWV 903, he provides a priceless contribution to posterity by graphically verbalising a Bach performance style practised by the man who proved to be the most influential keyboard composer and performer of the nineteenth century.
Franz Liszt in his demonic style is so highly regarded that he need not be bothered to understand a single work more or less correctly. He stormed through the Fantasy and Fugue as in a bacchanalian intoxication (the Fugue twice as fast as it is usually played - or can be played); he doubled the bass in the Fugue almost throughout, and added to this storm on tone unexpected sforzandi (for instance minims in the bass, bars 39, 40, 60, 64 etc.) now in this voice, now in that, which had the effect of random lightning flashes in a night sky, bursting all the more into the foreground than they were indicated by the Fugue's structure. 
The Lisztian Bach style, having achieved wide acceptance, persisted in the numerous Bach transcriptions of the late-nineteenth and early twentieth century by such figures as von Bülow, von Tausig, Busoni and others. It is from this mid-nineteenth century stance that a portion of open-eyed musicians and scholars of Liszt's own period recoiled. Marx was concerned with the necessity to preserve Bach's structure; he recognised their egregious distortion, and voiced his rejection of it in no uncertain terms.
On the other hand Marx conveys the fact that he does not find Griepenkerl's claims of authenticity satisfactory either. By dint of repeated issues of the edition since 1819, Griepenkerl's persuasive claims in his Notes and his own performance instructions, asserting the direct and untrammelled tradition passing from Bach's sons and pupils, had taken hold. This created a school of unquestioning 'tradition' that supported the literal stance of 'authenticity'.
Marx's letter was interpreted by Griepenkerl as an open challenge to a duel, and he promptly picked up the glove. His reply appears the following month, in the Allgemeine Musikalische Zeitung headed 'Noch einmal: J. S. Bach's Chromatische Phantasies'  Griepenkerl's letter opens with an appreciation of Marx's informed stature and respected authority, and goes on to re-assert his own known position:
In the case of older compositions, [however,] which have become historic, there is only one conception, namely the historically correct one, in so far as we can ascertain it. 
Griepenkerl's view in 1819 had been based on his unswerving belief that all the specific directions in his edition flowed without any obstacle at any point from the mind, spirit, pen and practices of Johann Sebastian, but now adds 'as far as we can ascertain it'. There was no such assertion or implication in 1819. The stance of "only one conception, namely the historical one" has been universally regarded in the twentieth century as the ideal result of arduous research in notetext sources and the data of notetext and performance practice. (See below re Curt Sachs and correctness.) Griepenkerl's avowal tacked onto his position of certainty "as far as we can ascertain it", 39 years after his publication of 1819, began, only in the latter years of the twentieth century, to be acknowledged as a central problem capable of shattering the foundations of the entire 'authentic' edifice.
By 1848, the universal expansion in interest, studies and performances of Bach's music, coupled with the inevitable accumulative effects of the inquiring spirit developed during the Enlightenment, brought about a heightened awareness of changing cultures and new areas of significance caused by these changes. The cultural horizon of this time extended the style of viewing products of a past era, and even Griepenkerl, who had spent his life in the staunch belief that he was the guardian of the master's original intentions, felt the need to allow a crack in the armour of historical certainty. For Griepenkerl does finally admit that the force of evolving concepts cannot be denied or stayed. Nevertheless, he withholds any hope of meeting Marx on a common ground.
Now of course, that time is past; Forkel's surviving students are too old, and every time the tradition is passed on, it loses some of its individuality and clarity. But one tries to save what one can, and do one's duty even if one disagrees with Herr Professor Marx. 
Griepenkerl then confronts the fashion of performance of his contemporary virtuosi in comparison with performance by Sebastian, his two sons, Friedemann and Emanuel, and Forkel. He adds:
One must have heard this, or one can never learn to play a fugue by J. S. Bach correctly. 
Griepenkerl's spirit is admirable and inspiring but his assertion that one "can never learn to play a Bach fugue correctly" if one has not heard Sebastian, Friedemann, Emanuel or Forkel perform fugues is daunting to even the most conservative of traditionalists. It benumbs any hope for posterity of ever approaching a valid performance of a Bach fugue; and as a basic hermeneutic principle it nullifies the prospect of interpreting, on any level, a masterwork of a past era with a sense of conceptual, structural and aesthetic validity and quintessential significance.
One wonders if Griepenkerl ever read the plays of Shakespeare or contemplated the paintings of Rembrandt to experience the profound levels of intellectual illumination and aesthetic wonder that works of this calibre - in which category he would be the first to agree Bach must be included - communicate to the minds and sensibilities of the changing cultures of posterity. Note that Griepenkerl's criterion is centred in the word 'correctly'. We are to see that this notion of correctness brought about both positive and negative conditions in later nineteenth-and twentieth-century scholarship and performance.
Whereas Griepenkerl's notion of a tradition appears to be narrowed down to a single path - in this case inherited-cum-single family/student aristocratic line - Marx's basic understanding involves the complexities inherent in the very conditions of discovering and attempting to follow a 'tradition'. As a result of Griepenkerl's accusations, Marx answers Griepenkerl's statement by listing the following alternatives in his reply published in the next issue (March 8,1848) :
... - here we reach the real point of contention - we must as Herr Professor Griepenkerl prescribes, throw ourselves into the arms of tradition. 'The old compositions/ he says, 'without their traditional interpretation, are a historical untruth...' Here we have a fundamental difference (and not for the first time) along whose lines our own era is split; tradition versus revelation, historic 'divine' right versus the right of common sense, dogmas vs. research, or whatever names are used for fundamental musical foundations and principles. 
In stating the fundamental difference in their positions, Marx faces the situation head on and describes the perspective of posterity vis-à-vis great art of the past.
Now, Forkel's time lies well behind us; his disciples are, by Herr Professor Griepenkerl's own admission, not all still able to play the work for us, and finally, it would not be so easy for all artists and music lovers to travel to Braunschwig to hear the Chromatic Fantasie played...if [for various early composers] traditions are lacking, then all these works would become historical untruths in our hands! 
Marx refers to the crucial position represented by the unconditional declaration of direct descent on the title-page of Griepenkerl's 1819 edition, and sets down a systematic evaluation of its claim to validity along with an analysis of its conceptual underpinning and the influence exerted upon others in accepting its stance and implications.
Now, let us consider this continuous chain from Sebastian Bach to us, that means a full century, and let us ask ourselves: Can a tradition be passed along in its full conception and content, can it be more than a general one, containing the varying individualities of every member of the chain? ... Can one be sure that in all particulars one is receiving the composer's intentions, or, much more likely, that of the conceptions and changes wrought by the middlemen?
And that is not all, even though I have assumed the best intentions on the part of everyone. But who knows how often incompetence, teaching, illustration and performance fall by the wayside to be replaced by alien style and led into quite different directions and results? Emanuel Bach, for example, whom Herr Professor Griepenkerl names as one of the intermediaries, has in his own compositions travelled so different a path that we may, with all due respect, question whether the ideas and their execution by his father remained alive in him. Forkel, the worthy writer and researcher, gives no proof in either his compositions or his biography of Bach that he has penetrated so deeply into the spirit of the master that he can be relied on as the ultimate authority beyond whom nothing more is to be said. 
Concerning Marx's questioning of Bach's sons and successors as ultimate guarantors of Sebastian's pure thought and style - it would, today also, be more beneficial than otherwise to be rather more wary and more selective of treatises by contemporaries of a Bach or other composers of the past. These writers of treatises, some of whom may indeed have been distinguished in their time as was Carl Philipp, write out of their own views, their own educational accretions and their responses and aspirations. For how wide a range or how fine a focus are their comments and instructions applicable? How certain are we of their infallibility, lack of bias and objectivity, the extent of their musical talent, intellectual precision or their overall and/or detailed absorption of teachers' instructions or their own forward-looking views? And even the supposed literal reproduction of period instruments by a later set of mental habits and sensibilities is a production emerging from inevitably different cultural roots and influences. We know that Carl Philipp's teachings were interwoven with both his father's views and his own very different productions in his compositional forms and structures.
This is not to deny the necessity to give full and careful consideration to period treatises. However, additional factors claim attention - a period treatise is not a set of commandments from on high. To quote and follow writers of the past, which is a style of exegesis much approved in modern times, does not necessarily provide an unalloyed coinciding of concept and stylistic performance manner with a period composition. The context of the views of succeeding cultures contains myriad nuances as well as outright new views, and here is embedded the significance of the forward-looking face of Janus.
 "Neue Ausgabe mit einer Bezeichnung ihres wahren Vortrages, wie derselbe von J.S. Bach auf W. Friedemann Bach, von diesem auf Forkel und von Forkel aus seine Schiiler gekommen."
 Mus. Ms P421 Fantasia chromatica pro Cimbalo di J.S. Bach. Recitat. Fuga.Bears the date "Im 6 December 1730", regarded generally as the oldest known MS of 903. MS D-BRD: B P421, pp. 2-24. 17.5 x 21 cm., 28pp.
 The term 'pianoforte' was in more general use than 'fortepiano'. The latter is popularly employed in recent times to distinguish the late eighteenth/early nineteenth century piano from that of the later nineteenth and the twentieth century.
 Wolff, C., 'New Research on Bach's Musical Offering', The Musical Quarterly,July 1971. vol. LVII. No. 3., pp. 379-408.
 Op. cit. [10c]
 J.S. Bach, Fantasia Chromatica, Trascrizione per Viola Alta di Zoltan Kodaly, Boosey and Hawkes, 1951.
 Marx, A.B., 'Sebastian Bach's chromatische Fantasie, Einige Bemerkungen von A.B. Marx', Allgemeine Musikalische Zeitung, Nr. 3 January 19 1848, pp. 34-42.
 Griepenkerl, F.K. 'Noch einmal: J.S. Bach's Chromatische Phantasie',Allgemeine Musikalische Zeitung, Nr. 7, 16 February 1848, pp. 98-100.
 Marx, A.B. 'Tradition und Prüfung', Allgemeine Musikalische Zeitung Nr. 10, March 8 1848, pp. 154-160
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