Leonardo da Vinci Society Newsletter

editor:  Francis Ames-Lewis


Issue 9,  November 1996

Recent and forthcoming events

The Leonardo da Vinci Society’s Colloquium on Leonardo da Vinci as a sculptor of the horse


The Colloquium publicised in the last issue of this Newsletter was held in the Board Room of the British Museum on 18 October 1996. Some twenty specialists, both in Leonardo studies and in Renaissance bronze techniques and metallurgy,  assembled for the discussion. The Colloquium had two facets: a series of four art-historical papers on relevant topics in Italian sculpture in Leonardo’s time, and detailed discussion of the small equestrian group owned by Dr L. Ven, of the Cercle des Amis du Quattrocento in Antwerp.

Dr J.V. Field (Birkbeck College, London) writes this report about the Ven equestrian group:

            One of the purposes of the colloquium was to provide an opportunity for display and discussion of a statuette (height about 30 cm), whose owner suggested that it might be a model for Verrocchio’s monument to Colleoni, and could be the work of Leonardo. There is no documentary evidence for a small metal or wax precursor to the Colleoni monument; so arguments had to turn upon the statuette itself.

            Mr Ven is a business man. His study of the statuette had been informed by great enthusiasm, and was presented with corresponding verve. However, it did not marshal evidence and arguments in the manner of an academic historian.

            The statuette was bought from a dealer in Rome in the 1890s, by Mr Ven’s great uncle. There is no earlier provenance. There had been no chemical analysis of the metal. The quality of the modelling and the nature of the detail argues strongly against the work dating from the fifteenth century. In particular, the armour that is shown is very unlike real fifteenth-century work. The Colleoni statue naturally has correct armour, and it is notable that the departures from it in the statuette are in those passages of the monument that cannot easily be seen from the ground.


            The method of construction, as revealed by X-ray photographs as well as by inspection of the pieces from which the statuette was assembled, is entirely compatible with a nineteenth-century date, and very unlikely for a fifteenth-century one. The opinion of the majority of the historians who examined the statuette, and heard Mr Ven’s arguments, seemed to be that, unfortunately, it is overwhelmingly likely to be nineteenth-century.  We shall have to look elsewhere for an example of sculpture by Leonardo.


Further to the Colloquium, Mr Ven’s equestrian statuette underwent metallurgical testing at the laboratory of Jean-Marie Welter, of Trefimetaux, Sérifontaine, France (who was a participant in the Colloquium) on 15 November. Mr Ven and Mr Welter spent the day testing the statuette with an analytical scanning electron microscope, to test the chemical composition of the alloy, and with a FT-infrared spectrometer (to study the patina). ‘The first result’, we hear from Mr Welter, ‘was that the alloy is brass and not bronze. We are still evaluating the details’. We expect to receive a full report in due course, but it may be noted that in his brief account of these preliminary findings Mr Welter did not confirm that the metal alloy allowed the possibility that the statuette could have been made in the fifteenth century.


The four specialist papers sought to set the examination of the Ven statuette in a wider context. Since the group is related to the Colleoni Monument by Andrea del Verrocchio in Venice, Professor Dario Covi (University of Louisville) gave a detailed account of the documents and other contemporary texts concerning this equestrian monument. A letter of July 1481 speaks of a lifesize demonstration model ‘which is a bella fantasia’; and visiting Venice in 1483 the Ulm Dominican Felix Faber wrote of a competition between three sculptors - perhaps Verrocchio, Bellano and Leopardi (who eventually carried out the casting of Verrocchio’s model). Three models were on view, one of wood covered with black leather, one of terracotta and the third, which won the competition, moulded in wax and ‘exquisitely shaped’. Verrocchio was resident in Venice in 1486, but he died in June 1488, bequeathing the final model, on which he had started work, to his assistant Lorenzo di Credi. The monument was finally set in place, on Leopardi’s plinth, in 1494, nearly twenty years after Colleoni had died.

            The second paper was given by Professor Chandler Kirwin (Guelf University, Ontario), on issues around Leonardo’s plans for casting the Sforza Horse. Extrapolating from his paper published in the book edited by Diane Cole Ahl and reviewed later in this Newsletter, Professor Kirwin discussed in detail Leonardo’s often tantalizingly elliptical notes on the Horse and the casting process that he was devising. He was especially concerned to define the progress of Leonardo’s thoughts on the evolving size of the horse. This he did through detailed examination of technical drawings in Madrid Codex II and at Windsor (RL 12358). Between April 1490, when Leonardo ‘...recommenced the horse’, and December 1493 he proposed an equestrian statue only slightly larger than life size. Professor Kirwin suggested that it was onlywhen Leonardo had successfully resolved a long series of technical problems associated with the casting process that he debated with himself during these years, that he decided to try to cast a colossus of 24 feet, or perhaps even 32 feet, in height.

            Professor Martin Kemp (University of Oxford) introduced a small wax model of a standing horse now in a private collection in Zurich. This model, which had generously been brought by its owner to the Colloquium for participants to study, has an excellent provenance from which it appears that it was formerly owned by Lodovico Sforza (Leonardo da Vinci’s patron for the Sforza Monument) and Alfonso d’Este. Professor Kemp compared the ‘insistent yet subtle’ anatomy and modelling of the wax horse with Leonardo’s drawings for the Sforza Horse, and in particular with the early drawings in silverpoint on blue prepared paper, such as Royal Library 12321, a sheet exhibited in the 1989 Leonardo exhibition at the Hayward Gallery (cat. no. 40). Since the wax model has all four hoofs on the base and is not active, it was perhaps an independent study rather than a modello for a bronze equestrian group.

            Finally, Dr Michael Kwakkelstein (University of Leiden) spoke about the so-called ‘Bust of Christ as a young man’, a terracotta bust recently exhibited at the Leonardo da Vinci: Scientist, Inventor, Artist exhibition at the Kunsthal, Rotterdam. Discovered in 1931 in a convent at Ascoli Piceno, this bust has been associated by Carlo Pedretti with a reference by Lomazzo to a ‘christo fanciullo’ by Leonardo that he owned in the late sixteenth century. Dr Kwakkelstein proposed, however, that the bust is probably the upper part of the figure of a Saint, perhaps St John the Evangelist, from a terracotta Lamentation group of the type modelled by Niccolė dell’Arca and Guido Mazzoni. There are parallels in life-size figure-sculpture of the time, such as the figure of St Eufemia recently identified as by Andrea Mantegna, for the modelling technique used in this bust. The expressive characterisation of the figure’s ‘moti mentali’ is, Dr Kwakkelstein suggested, beyond the range of a Verrocchio, and is comparable with the composite psychological efects of the Apostles’ heads in Leonardo’s Last Supper. He concluded that although an attribution to Leonardo himself cannot be confirmed, it should not be excluded.


Art and Science in the Italian Renaissance: Vitruvian Themes


The sixth in the series of annual symposia on ‘Art and Science in the Italian Renaissance’ organised jointly by the Leonardo da Vinci Society and the Society for Renaissance Studies will be held on Friday 31 January 1997, as usual at the Warburg Institute, Woburn Square, London WC1. The subject for the forthcoming symposium is ‘Vitruvian Themes’; the organiser is Dr J.V. Field. The following papers will be given:

Frank Zöllner (Hamburg), on ‘Vitruvian Man’; Paul Davies (University of Reading), ‘Marcus Vitruvius Pollio versus Lucius Vitruvius Cerdo: architecture in Renaissance Verona’; Vaughan Hart (University of Bath) and Peter Hicks (University of Cambridge), ‘Sebastiano Serlio and the illustration of Vitruvius’; J.D. Loach (University of Wales, Cardiff), on ‘Temporary architecture’; and J.V. Field (Birkbeck College, London), ‘Horas non numero. I make a botch / Of what is done far better by a watch’.


1997 Annual Lecture

The Society’s 1997 Annual Lecture will be given at Birkbeck College, University of London, on Friday 2 May 1997, at 6.00 pm. Dr Evelyn Welch (University of Sussex) will speak on ‘Leonardo da Vinci and the Ladies of Milan’. Her lecture will follow the AGM of the Society, which will take place at 5.30 pm. Further details will be circulated to members in due course.


Leonardesque News

An exhibition in London, Ontario: ‘Leonardo da Vinci: the Search for the Soul’

An exhibition with this title, curated by Dr Rolando Del Maestro, was held from 15 June to 1 July 1996 at the London Regional Art & Historical Museums, London, Ontario, Canada. The primary objectives of the exhibition were ‘to outline Leonardo’s method of innovative exploration related to the continuum of anatomical studies associated with the brain... [and] to provide a hands-on exhibition which allowed for an exploration of brain function’. The show was mounted to coincide with the 31st Canadian Congress of Neurological Sciences, also held in London, Ontario this summer.                                                      Dr Del Maestro is himself a neurosurgeon who, as a result of his professional work has become ‘acutely aware that there are areas of the brain clustered around the anterior third ventricle-hypothalamic region which, if disturbed, result in a profound change in the way that an individual perceives not only their outer but also their inner world’. Leonardo too was concerned to discover the site of the senso comune - his ‘search for the soul’. In the exhibition catalogue Dr Del Maestro proposes that this exploration started when Leonardo wrote on work was principally set in train when Leonardo started work on Royal Library 19059, the first of a series of minutely fine studies of the skull, writing ‘on the 2nd day of April 1489. Book entitled On the Human Figure’. In the skull drawings Leonardo consistently locates the senso comune ‘just above the optic chiasm in the region of the anterior portion of the cavity which we now call the third ventricle’. Later, in anatomical study started around 1508-9, Leonardo applied his experience of bronze casting to obtain a wax impression of the ventricular system of an ox (Royal Library 19127), He thus had a relatively accurate model on which he then located the ‘imprensiva’, the senso comune and the ‘memoria’.                                                    The exhibition consisted of books and facsimiles of drawings principally from Dr Del Maestro’s own library of Vinciana. Associated events included a series of three lectures on Leonardo and a ‘Leonardo da Vinci Gala Night’ to raise funds for the Brain Tumor Foundation of Canada.

Current Exhibitions in London, England

Unfortunately it was not possible to display the large international exhibition entitled Leonardo da Vinci: Inventor, scientist and artist, previously on view at the Kunsthal, Rotterdam, at the Accademia Italiana (see the announcement in issue 8 of this Newsletter). However, the exhbition of ‘Leonardo da Vinci: 100 drawings’ at the Queen’s Gallery, Buckingham Palace, reviewed in issue 8, is still on view. It closes on 12 January 1997. A further group of four Leonardo drawings, including his celebrated early ‘Bust of a Warrior’ and one of the series of drapery studies on linen that he made while in Verrocchio’s workshop, are included in the magnificent exhibition of Old Master Drawings from the Malcolm Collection, currently on view in the Department of Prints and Drawings gallery at the British Museum.

Further progress on the Leonardo Horse project

The President of LDVHI, Roger Enloe, has written to let the Society know that in June he opened negotiations with the Italian authorities on finding an appropriate site in Milan for the installation of the bronze horse currently in production at the Tallix foundry. A meeting was held with Ambassador Bianchieri, formerly Italian Ambassador to the USA and now Secretary-General of the Ministry of Foreign Affairs in Rome. Further consultations with curators and soprintendenti in Milan led to the conclusion that the best site would be at the Leonardo da Vinci Museum of Science and Technology. It is proposed that the Horse should be unveiled in its final location on 10 September 1999, exactly 500 years after the French invaded of Milan and drove Lodovico Sforza from power, and when Leonardo’s colossal clay model was destroyed when used for target practice by the French troops.                                                                        Meanwhile work continues at the Tallix foundry, north of New York City, on the casting of the colossal, 24-foot horse. Most of the $3,200,000 needed has been successfully raised. During the summer, foundry technicians enlarged the model threefold using a pantograph to produce a full-size, hollow model in plaster and clay. This will soon be disassembled into between ten and fourteen individual pieces that will be cast separately and welded together. The body of the horse will probably be cast in six ‘doughnuts’ each about 20 feet in circumference, since closed volumes maintain their shape in the casting process, whereas ‘plates’ might go out of shape causing problems in seamless welding. These sections will be welded together around a stainless steel armature needed especially to strengthen the two legs which carry the entire weight - perhaps as much as eighty tons - of the Horse.

Leonardo da Vinci’s Sforza Monument Horse: The Art and the Engineering                      

Edited by Professor Diane Cole Ahl (Lafayette College, Pennsylvania), and published in 1995 by Associated University Presses, Inc., this book presents the papers given at a symposium held at Lafayette College and the Dent Project Studio, Fogelsville, Pa. on 18-19 April 1991. The symposium was stimulated by Charles Dent’s enthusiasm for his Horse project, and the book’s foreword by the co-organiser Stephen H. Cutcliffe, is dedicated to Dent’s memory. The book, writes Cutcliffe, ‘is a printed memorial to the monument never case and a preview of the one planned by Charles Dent...’. It is a beautifully produced and richly illustrated collection of contributions important to our understanding of Leonardo da Vinci’s ambitions and designs for the Sforza Horse.                      The nine contributions address an impressive range of issues relating both to Leonardo’s work on the Horse and to more recent reconstructions of the monument. The first group of papers sets the context for the Sforza Monument. In his ‘keynote address’ Carlo Pedretti reviews the political background to the French invasion of Milan, and identifies the site of the destruction of the model as the foundry on Leonardo’s property not far from Sta Maria delle Grazie and just inside the Porta Vercellina through which the French troops entered Milan. On the basis of slight sketches in Ms.H (of 1493-4) he also interestingly proposes that the plinth was to have been much lower than is usually believed, and possibly associated with a fountain. Dario Covi provides a valuable and informative survey of the development and propaganda meanings of the equestrian monument, which helps the reader to perceive the place of the Sforza Monument within the Renaissance tradition. In the third paper, Ellen Wells discusses the role of horses in Italian Renaissance court life: at first an instrument of warfare, the horse became by around 1550 an essential property of the courtier. This change provides another facet of the framework within which Leonardo sought to design a perfect horse on the basis of his detailed study of the anatomy and proportions of horses owned by such Milanese courtiers as Galeazzo da Sanseverino.                       The central group of three papers focuses specifically on Leonardo’s design and technological work for the Sforza Monument. Martin Kemp’s detailed study of the surviving drawings that chart Leonardo’s ‘program of research’ defines the principal phases of the evolution of the design. This is a keen analysis of the functions of the Sforza horse drawings, showing how Leonardo interrelated graphic technique and handling with the exploratory intention of each study and brought together his joint concerns with art, science and technology in an ideal synthesis. Virginia Bush suggests that Ludovico Sforza may have contemplated erecting two colossal equestrian monuments, Francesco Sforza’s complemented with another that was to commemorate Ludovico himself, on the ravelin of the Castello Sforzesco, as an expression of his grand political pretensions. In an interesting review of the rise and fall of the Sforza she characterises Ludovico as a usurper and an international troublemaker, and suggests that ‘Leonardo’s monument was in keeping with Ludovico’s extraordinary ambitions’: both were bound ultimately to fail. In a fascinating contribution, Chandler Kirwin discusses the development of Leonardo’s technological understanding of bronze casting. He shows that in his investigations of machines of war, Leonardo acquired a great deal of expertise about cannon design and casting. This technical skill led him to devise a casting process that had much more in common with large-scale weapons manufacture than with the techniques for casting bronze sculpture in the quattrocento. In places highly technical, this study leads smoothly into Richard Polich’s discussion of the very different casting techniques currently in use in the reproduction of Leonardo’s colossal horse.                                                 The last group of three papers deals with reproductions of sculpture, and especially of the Sforza Horse. Jack Wasserman intriguingly surveys the replication of sculpture, both Classical and Renaissance, in recent centuries. He shows that between the later sixteenth and the mid-nineteenth century Renaissance sculpture was scarcely ever reproduced in three dimensions. From around 1850, however, the production of plaster casts of Renaissance sculpture opened the flood-gates for the replication of sculpture on both full scale and in reduced size for the tourist market. He ends his paper with comment on the contemporary full-size reconstructions of the Sforza Horse that form the subjects of the book’s last two contributions. The second of these is of course the bronze being cast at the Tallix foundry, which is central to the discussion by Richard Polich of the insuperable technical problems that Leonardo da Vinci would have faced had casting of his model ever gone ahead. Polich demonstrates persuasively that at that time technology was inadequate to the task, and Leonardo’s cast was doomed to failure. Perhaps it is just as well that Lodovico Sforza had sold the bronze intended for the horse to Ercole d’Este for casting cannon. The first reconstruction is a full-scale equestrian group cast in synthetic, fiber-reinforced plasic. This was unveiled in 1989 in Nagoya City, Japan. Hidemichi Tanaka, whose brainchild it was, discusses the design process in which an ideal composite drawing based on Leonardo’s various sketches was made by computer simulation. A six-foot clay model based on this drawing was enlarged fourfold; from this the plastic cast was produced in fifteen sections. The equestrian statue, which is white rather than in simulated bronze or gold, includes a somewhat fanciful reconstruction also of Francesco Sforza in the saddle. Like Polich, Tanaka concludes that Leonardo could not have succeeded in casting his full-scale model in bronze. He suggests that when Leonardo referred to the use of the bronze for cannonry, writing that ‘of the horse I will say nothing because I know the times’ he may have recognised that casting his colossal horse would be impossible.


The Leonardo da Vinci Society


Proposals for future events - conferences, symposia, lectures, or other activities that the Society might sponsor or undertake - are always welcomed by the Committee. Please write to any of the officers listed below if you have any suggestions to offer. The Committee is also anxious to recruit new blood to its membership, so if any readers have ideas to contribute and would be interested in serving, please will they let us know of them.


            President: Professor Martin Kemp, Department of History of Art, University of Oxford, Beaumont Street, Oxford, OX1.2PH

            Vice-President: Dr. Francis Ames-Lewis, Department of History of Art, Birkbeck College, 43 Gordon Square, London WC1H 0PD

            Secretary/Treasurer: Dr Richard Schofield, Department of Art History, University of Nottingham, University Park, Nottingham NG7 2RD, UK. 

            Please send items for publication to the editor of the Leonardo da Vinci Society Newsletter, Francis Ames-Lewis, Department of History of Art, Birkbeck College, 43 Gordon Square, London WC1H 0PD; FAX 0171.631.6107; Email: f.ames-lewis@hart.bbk.ac.uk