Late in 1506, in Milan, Leonardo engaged in intensive anatomical investigations. He revived his interest in artistic anatomy and returned to a manuscript he had begun close to 20 years earlier, the so-called Anatomical Manuscript B, now in the Royal Library at Windsor.
The history of Leonardo’s anatomical notebooks in the wake of his death is complex, but the history of Anatomical Manuscript B is somewhat clearer. Thomas Howard, Count of Arundel, likely brought it to England sometime before 1630. By 1690, it had entered the royal collection, where it is still kept. At some moment of its early history, it was dismantled, and only in 1979 it was reassembled. The last page of the reassembled Anatomical Manuscript B is a famous folio in which Leonardo illustrates the anatomy of a kneeling figure and sketches the outline of his anatomical treatise (figs. 1 and 2).
This folio (Windsor, Royal Library 19037r) is typical of Leonardo’s working style. Around 1489 he started to write his plan for an anatomical treatise on the side of the sheet that is today the verso of the folio, ran out of space, turned the page and continued to write on the side that is today the recto. He did not bother to fill the bottom part of the sheet and the folio remained that way, the lower part blank, until he returned to it sometime after 1506. At that point Leonardo wrote a description of the actions of muscles, tendons and bones of a man or a woman in the act of kneeling, and he also made two anatomical drawings.
He was especially interested in the role of the sartorius and semitendenous muscles, which control the external rotation of the thigh and knee (thus the etymological connection with the Italian sarto [tailor] who crossed one ankle over the other knee to support handwork). They are emphasized prominently in both drawings. The awareness in the drawings of particular, specific muscles as such as these suggests that Leonardo would have known these structures through dissection, but they also betray less of an interest in the dissected limb per se and more in explaining the mechanics that allow it to move. He clarifies this aim in the following passage written toward the bottom of the page:
Different muscles are uncovered in the different movements of the animals and there are different muscles which are hidden in such diversity of movement. It is necessary to make a long treatise on this subject for the purpose of understanding the regions injured by wounds and also for the sake of sculptors and painters.
In other words, muscles change their shape and visibility based on movement, and that knowledge (or scienza, in Renaissance terms) has different applications for pathology as well as for art making.
In another passage, recorded in the Libro di pittura (chapter 180), Leonardo reminds us that “a good painter has two chief objects to paint, man and the intention of his soul; the former is easy, the latter is hard, because he has to represent it by the attitudes and movements of his limbs.” One revelatory posture of how the exterior reveals the interior is that of a kneeling figure, which he represented in numerous paintings. By the time he drew the anatomical drawings of a kneeling figure, he had depicted an array of kneeling figures: angels in the [Annunciation](http://www.googleartproject.com/collection/uffizi-gallery/artwork/annunciation-leonardo-da-vinci/324474/) and the Baptism; numerous bystanders in the [Adoration of the Magi](http://www.googleartproject.com/collection/uffizi-gallery/artwork/adoration-of-the-magi-leonardo-da-vinci/328512/); and a kneeling Virgin in the Louvre [Madonna of the Rocks](http://www.louvre.fr/en/oeuvre-notices/virgin-rocks). At this very time, he also had begun the compositional studies for the so-called kneeling [Leda](http://www.universalleonardo.org/work.php?id=341). In all cases, kneeling plays a crucial role in the unfolding action.
People in the early modern period knelt more often than we do. Documents from the period make clear that kneeling and genuflection played a key role in the expression of devotion, in decorous behavior, and in recognition of higher authority—whether a pope, a saint, or a queen. It seems that in this drawing Leonardo investigates the action of kneeling—how the bones, muscles, and tendons work together to allow the human body to go on bended knees—to reveal the inner states of people in specific situations of devotion or submission.
In creating his paintings with kneeling figures, Leonardo followed his own precept: “First study science and then follow the practice born of that science” or: “First follow knowledge, and then follow the practice (arte) born of that knowledge.” It has become commonplace to refer to Leonardo as both an artist and a scientist, to think of him as active in these two fields seen now as disparate. And yet, for the Renaissance as a whole, and for the sixteenth century in Italy in particular, the terms would have been more roughly synonymous with arte and scienza: mechanical skill or technique on the one hand, and more systematic knowledge or even epistemology on the other—notions drawn from classical writings of philosophers such as Aristotle. A separation between what we now think of as ‘science’ and ‘art’ would have been nearly non-existent.
Leonardo explores the intimate bonds of art and scienza, their inseparability here, laying out on one side of the page the structure for an overall study of human anatomy, then returning, decades later, to the same page to explore how that knowledge and study can play an essential role in the creation of lively and powerful physical works of art.
Leonardo da Vinci, The muscles of the leg, Anatomical Manuscript B, Windsor, Royal Library, 19037r. (Royal Collection Trust / © HM Queen Elizabeth II 2012).
Leonardo da Vinci, Outline of an anatomical treatise, Anatomical Manuscript B, Windsor, Royal Library, 19037v. (Royal Collection Trust / © HM Queen Elizabeth II 2012).