Scientific Research

Arthur Lucas

Arthur Lucas was the head of restoration and conservation of the National Gallery in London. Bolleurs knew Arthur Lucas well and since the latter saw the possibilities and the quality of the painting he offered to clean it and restore it, thus revealing the abundance of plants and foliage that surounded the kissing babies. He mentioned in his report that he had to put in great effort in order to remove the darkened and hardened varnish with which the painting seemed to be covered with in the past. Maybe even to censor the meaning of the image, Arthur Lucas remarks.

Herman Khun

Dr. Herman Kuhn was a renowned researcher and chemist who wrote the first report on the chemical composition of the gesso layers and the paint pigments. Kuhn's expertise is held in great esteem by, amongst others, Maurizo Seracini who has also wrote an important report on the painting, following up on Herman Khun's work.

Martin Kemp

Professor Martin Kemp has looked at the painting thoroughly he has been supportive to Robert Bolleurs and was willing to collaborate with the production team that made an hour-long documentary on the painting for Fulcrum T V. Martin Kemp saw interesting aspects, took the painting to the same work that Carlo Pedretti had mentioned - the London version of the Madonna of the Rocks- and reinstated the first preliminary sketch in the corner of a larger Windsor sheet as a genuine work by Da Vinci therefore linking the painting with the Leonardo concept. Martin Kemp has never said or written the last word on it, in his last conversation with Robbert Bolleurs he promised to keep in touch: 'if there is ever a new development Robbert, let me know and I'll look into it'. This book is full of new developments, and we deeply appreciate Martin Kemp's support for the project through the years.

Pascal Cotte

Prof. Pascal Cotte has investigated the panel n Paris in his Lumiere Technology studio. Cotte used comparison methods with existing data he had gathered in the previous years. He concluded on one hand that he missed the "tres fines details", which, in his opinion, ought to be present in autograph Da Vinci paintings, but he was surprised by the build up of the coloured shadows that were achieved according to Da Vinci's color and shadow theory and therefore an idication for Leonardo's personal influence and touch.

Maurizio Seracini

Dr. Maurizio Seracini took the trouble of taking his laboratory to the Netherlands to perform an investigation on the panel during a week in August 2017. His technical overview is unsurpassed. His report is included in the book. Maurizio Seracini was unsure of the dating of the painting which doubts arose from the interpretation of certain yellow pigment used in the painting. Milko den Leeuw (see below) has cleared up this issue in his report from 2022. Maurizio Seracini discovered the original Aldobrandini numbering and description applied by Aghucci, the art specialist for cardinal Aldobrandini, himself. An inscription which was hidden under the black paint applied on the back of the panel, stating: no.39 Leonardo da Vinci.

Carlo Pedretti

Professor Carlo Pedretti too looked thoroughly at the painting and corresponded with Robert Bolleurs on his findings. His letter from 1979 reads like a recognition as he writes (the letter is included in the book), 'I have no hesitation to recognize the same hand that has painted the second version of the Madonna of the rocks in London'. Unfortunatly Carlo Pedretti passed away before the research was finished.

William Emboden

Professor William Emboden was a pupil of Carlo Pedretti. To illustrate the level of expertise we quote Carlo Pedretti's last sentence in his preface to Emboden's seminal work 'Leonardo da Vinci, On plants and Gardens': "Professor Emboden's training as a scientist does not prevent him from approaching his subject with the trepidation of a poet, and the result is indeed that happy combination of knowledge and fantasy that characterises soo much of Leonardo's writing on Nature. Only a few can achieve this and Goethe was one of them. William Emboden gives his expert opinion on the various plants that are depicted in the kissing children, culminating in a revealing report, but above that he is formulating his opinion on the essence of the painting when he concludes: "there is a pervasive contained majesty without decorative elements" in this painting. Although William Emboden passed away in 2016, we thank him for his insight and his report.

Janneke Verwey

Drs. Janneke Verwey was the first to write an interesting but modest book about the painting and her views on perspective and symmetry that is obviously hidden in the painting, although a very personal account it laid the groundwork for a far more in depth analysis of Leonardo's vision on perspective and symmetry as later extended in the concept book of Milko den Leeuw.

Milko den Leeuw

Milko den Leeuw and his partner Ingeborg de Jongh have been deeply involved in the project. The foundation BECI has commissioned a restauration- and technical overview resulting in a report dated 2022. In the beginning of the year 2024 the foundation has commissioned a concept book picturing the painting into a wider perspective, seeking a broader support for the painting as a work of Da Vinci and his Studio. We thank Milko den Leeuw for his in deep analysis of the yellow pigment used in the painting and thus placing this panel in the correct timeframe.

Important other observations are the use of triple lightning, meaning that the painter has suggested three different directions from which the main characters are lit, his presentation of how the paint layers are constructed and his contribution to the debate on perspective and symmetry that can be extracted from the image. Most interesting are the triangular forms that can be traced back to Luca Pacioli and Leonardo da Vinci and the dissecting lines through the ear, indicating that one theme imbedded in the painting can be music, tempi and pause as often brought forward by Isabel d'Este.

"There's a page at Windsor, which is mainly pupils' drawings, while it is said to be all pupils' drawings. But I have looked again at the drawing in the bottom right hand corner and I think it's absolutely Leonardo. It's simply not pupils' work. It's drawn left-handed, you can see the left-handed shading, it even hooks back at the end. So I think we have reinstated a drawing. This is now, I think, on the sheet of pupils work, Leonardo doing a little sketch, which is the sketch which says that this motif of the children caressing is a Leonardo motif." (Prof. Dr. Martin Kemp)