Italian stringed keyboard instruments and simple geometry:  Some new developments at the Russell Collection of Early Keyboard Instruments


Grant O’Brien


Full details of the analysis of the original state of this instrument can be found in an article written by me:  Towards establishing the original state of the three-manual harpsichord by Stefano Bolcioni, Florence, 1627, in the Russell Collection of Early Keyboard Instruments, Edinburgh’, The Galpin Society Journal, 53 (2000) 168-200.  ISSN 0072.0127.



The triple-manual harpsichord signed by Stefano Bolcioni, Florence, 1627

          The harpsichord in the Russell Collection of Early Keyboard Instruments at the University of Edinburgh signed ‘STEFANVS · BOLCIONIVS · PRATENSIS · F · A·D · M·D·C·XXVII  F’[15] is a good example of an instrument which has had a chequered history and which, in its present state, does not in any way represent its original nor any intermediate historical state.  It presently has a disposition of 2 x 8', 1 x 4' with three uncoupled keyboards and three registers, one per keyboard.  It has an elaborately-decorated outer case in a kind of Italian vernis-martin mannerist style, and a complex stand in the style of Louis XIV (see Figure 8).  A photograph of this instrument appears in the catalogues of Leopoldo Franciolini[16] with three keyboards and the same outer case but with a totally different decoration and stand[17].  It is clear that the present state is totally inauthentic and dates from a ‘re-working’ of the instrument around the time when it was offered for sale by Franciolini at the end of the nineteenth century.  Because of the extent of the drastic alterations to the instrument it has hitherto been impossible to establish the original compass, disposition, scalings and pitch of this instrument with any certainty[18].

          In the short time I have available here I can only present the highlights of the analysis of this instrument, but I will publish the full analysis in the next issue of The Galpin Society Journal[19].  The analysis below is an attempt to show how the original dimensions of the baseboard used by Bolcioni to design and construct this instrument can be determined using the Florentine soldo[20], and comparison with the only other surviving Bolcioni harpsichord in the University of Yale.  Once the baseboard dimensions have been determined, this can be used to estimate the original scalings, and further analysis also allows the determination of the original compass.  All of these analyses rely on the initial determination of the unit of measurement used in its design and construction, and the subsequent use of this unit to help to determine the scalings and compass.  This is a procedure not previously applied to this radically-altered instrument.

Triple-manual harpsichord by Stefano Bolcioni, Florence, 1627

Figure 8 - ¾-view photograph showing the present state

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          The 1627 Bolcioni harpsichord has unusual sloping cheekpieces beside the keyboard instead of the usual keywell scrolls.  Close examination shows that these are not original but have been added on with lap joints to the main spine and cheek sides.  Comparison with the Yale Bolcioni shows that, in order to have used similar cheekpieces, there must now be about 20½mm missing from the front of the baseboard of the Edinburgh harpsichord.  Adding this missing 20½mm results in the measurements given in Table 2 which are shown in the left-hand part of the diagram of Figure 9.

          The value of the Florentine soldo used in the Edinburgh Bolcioni can be calculated in the usual way.  The tangent of the tail angle is tan 38½º = 0.795 ≈ 0.80 = .  The ratio  suggests that the two orthogonal components of the triangle that form the tail angle are 8 soldi and 10 soldi which, mathematically, would form an angle of 38.66º, which is very close to the measured angle of 38½º.  A summary of the original measurements of the baseboard, baseboard construction lines and the case height in soldi is given in Table 2, where the lengths of the soldo calculated from each of these are shown at the right:


                                                                                    Measurement          Local                                       Length of

                                                                                                 in mm          unit                                            soldo

                    Tail angle component parallel to spine:               273½    =    10 soldi                    gives             27.35

         Tail angle component perpendicular to spine:                  220    =      8 soldi                    gives             27.50

                                             Spine (long bass side)*:             1981½    =     72½ soldi                 gives             27.33

                                                      Baseboard width:              756½     =     27soldi                 gives             27.34

                                        Cheek (short treble side)*:              537½     =     19soldi                 gives             27.33

                                                     Case sides height:                 219     =       8 soldi                   gives             27.38

                            Case front to nut line (bass side)*:             164½      =       6 soldi                   gives             27.42

                          Case front to nut line (treble side)*:             273½     =      10 soldi                   gives             27.35

                           Case front to belly rail (bass side)*:            391½      =      14soldi                gives             27.31

                         Case front to belly rail (treble side)*:            373½      =      13soldi                gives             27.33

                                                                                Totals:     5191       =    189soldi                 Average:     27.345mm

*These measurements have each been corrected by adding 20½mm.

 Table 2 - Original case measurements and the calculation of the Florentine soldo

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          This calculation gives a value of the soldo that compares with a value of 27.29mm found for the 1631 Bolcioni harpsichord in Yale University, a value of 27.401mm found for the Francesco Poggio virginal discussed above, a value of 27.341mm given by both Diderot (1751) and Krünitz (1788)[21], a value of 27.408mm given by Larousse[22] and the value of 27.53mm given by Colonel Cotty (1819)[23].  The similarity to one another of the values of the soldo found for the two Bolcioni harpsichords, and the similarity of these to the values given in the historical sources of metrology, confirms that they were all made in Florence using the Florentine braccio and soldo, and this fact helps to confirm that the instrument was indeed made by Bolcioni[24].


 Original baseboard dimensions without the case sides, Bolcioni harpsichord

Figure 9 - Baseboard measurements in millimetres (left) and

in units of the Florentine soldo used by Bolcioni = 27.345mm (right)

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          The shaded portion at the front of the baseboard seen in Figure 9 shows the amount which seems to have been removed in order to accommodate an intermediate state C/E to c3 keyboard with pedal pull-downs and short keylevers.  The various lines shown are scribed on the baseboard and indicate the original position of the nut, and the original position of the sides of the lower belly rail.  Clearly, if my assumption about the scroll of this harpsichord having originally been the same as that on the University of Yale Bolcioni so that 20½mm were removed from the baseboard of this instrument, the nut and the belly rail were positioned using simple integers and fractions of Florentine soldi as would be expected.

          Figure 10 shows a schematic representation of the cheek section, and of the probable original form of the keywell for the Edinburgh Bolcioni.  Here the keywell scroll of the Yale University Bolcioni harpsichord of 1631 has been added on at the point where the present join in the cheek begins (dashed line) and the batten in front of the baseboard of the Yale University Bolcioni has been drawn in (shaded).  An added section 20½mm wide (shaded) has had to be added to the length of the baseboard in order to accommodate the Yale cheek piece as discussed above.


Schematic section and cheek views, Bolcioni harpsichord

Figure 10 - Schematic representation of the cheek section[25] and the probable original form of the keywell section

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          The present boxslide registers, although cut in half longitudinally, are almost certainly original.  The top sections of both registers survive, and both have marks made near the jackslots made with a sharp pointed tool to locate the string directly above the mark.  These marks appear, from their irregular spacing along the registers, to indicate each of the notes c and f throughout the compass[26].

          Figure 11 indicates one of the registers in its present orientation at the top of the diagram, and the same register rotated through 180º in what is likely to have been its original orientation.  If the disposition of the two registers of the Edinburgh Bolcioni was the same as that of the 1631 Bolcioni in the University of Yale then this would be the register located nearest to the player which clearly, from the position of the indentation markings on the right-hand side of the jackslots, would have plucked the short set of 8' strings.


  Register in its present and original orientation, Bolcioni harpsichord

Figure 11 - One of the boxslide registers in its present position (top diagram)

and in its likely original orientation (bottom diagram)

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          In the present orientation of the register (top part of the diagram), the compass implied by the construction marks makes little sense and it appears that the registers have been turned end-for-end to give the notes and compass shown in the lower part of the diagram.  The compass implied by the marks on the register in this orientation is therefore clearly an enharmonic compass from C/E (broken octave) to c3 with two keys below the low C which could be tuned to any note required by the music in a manner similar to that adopted for the lower diapason notes of the theorboed lute.  I have assumed here that these keylevers would play strings tuned to G1 and A1 but they might have played any of a number of different notes[27].

          For various reasons it seems most likely that the front of the keyboard had a width of 29 naturals.  If these 29 naturals had a width designed by Bolcioni to be 25 soldi = 684mm, then the resulting span of the keyboard would be 495mm, intermediate between the 3-octave spans of the other Bolcioni instruments which vary from 488mm to 512mm[28].  A 25 soldi keyboard width would leave a space for the keywell scrolls and keyblocks of about 36mm on either side of the keyboard[29].  Figure 12 shows the compass and probable original arrangement of keylevers for this harpsichord.


Original keyboard layout, Bolcioni harpsichord

Figure 12 - Original compass and probable original key arrangement

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          In order to resolve the problem of deciding which of the soundboard markings belong to the original state of the instrument, a kind of string-band strip was made of the indented construction markings beside the jackslots on the registers[30] and this was used to search the soundboard area for signs of marking out. Holding it perpendicular to the spine and moving the string-band strip across the soundboard area showed clearly and unambiguously that there are similar construction indentations made with a sharp pointed tool on the soundboard corresponding to each of the register construction marks for the short string positions[31] for the notes c and f.  The positions of these markings were measured out and transferred onto the diagram of the instrument.  The position of the bridge found from the construction marks on the soundboard forms a smooth curve on the diagram of the baseboard which is quite accurately parallel to the bentside.  The c2 scaling of 300.9mm found using this method is very close to 11 Florentine soldi = 300.8mm suggesting that 11 soldi was the design scaling used by Bolcioni when laying out the construction marks for the 8' short string lengths (see further the graph of the original scalings shown in Figure 15).

          In a similar way the position and length of the long set of 8' strings was drawn on the diagram of the baseboard of the harpsichord, and the length of the long set of strings was measured in a similar way.  Similarly the plucking points were measured by assuming the same plucking directions as in the Yale Bolcioni harpsichord (see Figure 16).

 Original layout and string scalings, Bolcioni harpsichord

Figure 13 - Original scalings and string positions for the short 8' strings

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4

Original plucking points, Bolcioni harpsichord

Figure 14 - Original plucking points for both sets of 8' strings

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          The string scalings and plucking points for both sets of 8' strings as measured using the drawing programme are given in Table 3 rounded off to the nearest half-millimetre[32]:


                                           Long 8'                                                      Short 8'

                                       String            Plucking               String               Nominal                  Plucking

                                  length              point                  length             string length               point

                                       mm                  mm                     mm             mm         soldi                 mm

                   c3           157½                 98                      150½          150.4                          80

                     f2            236                  113                     225½                                                   94

                     c2           313½                123                      301            300.8        11                   105

                     f1           462½                141                      446                                                   121

                     c1             631                  154                      606            601.6        22                   133

                     f               960                  171                     923½                                                 150

                     c            1252                 183                    1215½          1203        44                   162

                      F            1557                 202                     1536                                                  180

                  C/E          1578                 204                     1557           1559        57                   182

                  [G1]            1624                 208                     1603           1600       58½                 186

 Table 3 - Estimated original scalings and plucking points

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4


          The scalings of the short strings, clearly the ones used to design this harpsichord by Bolcioni, are plotted in the graph of Figure 15.  A straight line has been added to the plotted scalings which corresponds to accurately Pythagorean scalings based on c2 = 11 soldi = 300.8mm.  This graph shows both that the reconstructed scalings obtained in Figure 15 were designed to be Pythagorean all the way from the bass bridge mitre right up to the top note, and that these scalings were almost certainly based in a design by Bolcioni with a short c2 = 11 soldi (or c1 = 22 soldi, etc).  Taken together these two facts give added confidence in the accuracy of the reconstruction of the scalings of this instrument.


Original string scalings, Bolcioni harpsichord

Figure 15 - Graph of the original scalings of the short 8' strings

Three-manual harpsichord by Stefano Bolcioni, Florence, 1627

Russell Collection of Early Keyboard Instruments, Inv. No. HT1-SB1627.4



[14] Both Horace Doursther, Dictionnaire universel des poids et mesures anciens et modernes, (Brussels, 1840) and Giovanni Croci, Dizionario universale dei pesi e delle misure in uso presso gli antichi e moderni con ragguagliò ai pesi e misure del sistema metrico, (The Author, Milan, 1860) give a value 262.01mm for the piede in Naples.

[15] See Sidney Newman and Peter Williams, The Russell Collection and other Early Keyboard Instruments in Saint Cecilia’s Hall, Edinburgh, (Edinburgh, 1968) Catalogue Number 4, frontispiece, viii, 8-9.  The new Russell Collection inventory number of this harpsichord is HT1-SB1627.4.  A data sheet on this harpsichord, published for the University of Edinburgh by the Friends of St Cecilia’s Hall and the Russell Collection, is available from the Russell Collection.

[16] Edwin M. Ripin, ‘The instrument catalogues of Leopoldo Franciolini’, Music Indexes and Bibliographies, Vol. 9 (New Jersey, 1974) Number 32, Catalog 6, Series A, page 70, and Photograph 29, page 127.

[17] There can be no doubt that it is the same instrument which is depicted in this photograph.  Besides the evidence provided by the identical cutting-down of the cheekpieces, the three keyboards and the folds in the lid flap, there are now filled holes in the top of the case and nameboard of the Russell Collection harpsichord for the ivory studs in each of the positions clearly visible in the Franciolini photograph.

[18] Reports in the Russell Collection archives by both John Barnes and Denzil Wraight attempting to use conventional analysis on this harpsichord failed to establish its original compass, string scalings and case measurements.

[19] This is the second part of the article, the first part of which has already published by me.   The use of simple geometry and the local unit of measurement in the design of Italian stringed keyboard instruments:  an aid to attribution and to organological analysis’, The Galpin Society Journal, 52 (1999) 108-171.

[20] As shown above in the discussion of the virginals by Poggio, the unit of measurement used in Florence was the braccio equal to about 548 to 551mm.  The most common division of the braccio was 1 braccio = 2 palmi = 20 soldi.

[21] Denis Diderot and Jean Henri le Rond d’Alembert, ‘Pied’, Encyclopédie ou dictionnaire raisonnée des arts, sciences et métiers (Paris, 1751-65) 562-563 and Johann Georg Krünitz, Öconomische Encyklopädie oder allgemeines System der Staats-, Stadt-, und Landwirtschaft, in alphabetischer Ordnung, 15 (Joseph Georg Traßler, Brünn, 1788) p. 519-22 both give lengths as 1440-th parts of the Paris pouce.  The length of the Florentine braccio and soldo were calculated by me using the value of the length of the French pouce given by Colonel Cotty, Aide-Mémoire (p. 896 - see footnote 12).  My thanks to John Koster for pointing out the Krünitz source to me.  Krünitz clearly bases his values on those given by Diderot.  He uses the same system of 1440-th parts of the French pouce, and gives exactly the same values as Diderot which were published almost 40 years earlier.

[22] See: Pierre Larousse, Grand Dictionnaire, (Paris, 1874) who gives a braccio with 20 soldi of length 548.17mm.

[23] Colonel Cotty, Aide-Mémoire a l’usage des officiers d’artillerie de France, 2 (Paris, 1819) 896-7 gives a length of 550.6371mm for the braccio da terra divided into 20 soldi.

[24] Unpublished work by me on the instruments of the Florentine makers Francesco Poggio and Bartolomeo Cristofori shows, not surprisingly, that the same Florentine soldo was used in the construction of the instruments of these makers as well.

[25] The moulding shown here on the outside of the case just below the top cap moulding is on the inside of the case everywhere else except for the cheek.

[26] The single-manual harpsichord by Stefano Bolcioni of 1631 in the Yale Collection of Musical Instruments, New Haven, Conn, Cat. No. 4889.72 has similar indentation markings on the top surface of the registers for the notes c and f.  In addition the top of the bridge on this instrument also has indentation markings for each of the c and f notes.

[27] F1 and G1 used as roots to major chords in key signatures with only one accidental are perhaps the most likely possibilities from a strictly musical point of view.  However, as will be seen below, the original scalings were clearly designed by Bolcioni to be accurately Pythagorean right down to the point where the bridge mitre occurred.  It is clear from the graph shown in Figure 15 that the scalings of the assumed note G1 is foreshortened by almost exactly a full octave relative to the Pythagorean scalings based on c2 = 11 soldi = 300.8mm.  For a maker who was clearly concerned that the scalings of his instrument should be accurately Pythagorean, it seems unlikely that he would have chosen to tune the bottom string to a note which was foreshortened by a whole octave plus a major second (a major ninth).  In simple terms this means that a string of this length tuned to a pitch as low as F1 would be very slack and would have a sound with a very poor musical quality.

[28] The 3-octave span of the virginal in Munich with a namebatten with Bolcioni’s signature and the date 1629 has a 3-octave span, reported by Hubert Henkel, Besaitete Tasteninstrumenten, (Erwin Bochinsky, Frankfurt-am-Main, 1994) 294, of 512mm.  This is very large in relation to the 3-octave span of other historical instruments.  If Bolcioni had designed the keyboard of the Edinburgh harpsichord to have a width of 26 soldi = 711mm, then the 29 naturals would have had a 3-octave span of 515mm, a value even larger than the Munich virginal and considerably larger than the normal 3-octave span of most Italian instruments which is usually about 500mm.  Indeed the 3-octave span is a value determined by the average size of the human hand rather than any desire on the part of the maker to use a convenient number of measuring units.

[29] If the keywell cheekpiece scrolls were of the same thickness as on the Yale 1631 Bolcioni harpsichord of about 7mm each, then the keyblocks would have had a thickness of about 29mm each.  This value has been assumed when drawing the diagram in Figure 16.

[30] For a discussion of the use of the string-band strip method for Flemish and in particular for Ruckers instruments see my article ‘The determination of the original compass and disposition of Ruckers harpsichords’, Colloquium.  Ruckers klavecimbels en copieën, (1977) 38-47 and my book Ruckers.  A Harpsichord and Virginal Building Tradition, (Cambridge University Press, Cambridge, 1990) 173-5.

[31] As mentioned in footnote 26 both the registers and the bridge of the 1631 Bolcioni harpsichord at the University of Yale have indentation markings for the c and f notes.  It is therefore not surprising to find indentation markings on this harpsichord underneath the bridge as well.  Clearly it is impossible to say if there are indentation markings underneath the bridge of the Yale instrument.

[32] These have been quoted here to the nearest half millimetre, but were measured by the drawing programme to an accuracy of a tenth of a millimetre.

Click here to read the next chapter