On the Fabric of the Human Body, Books III and IV

The magic of Vesalius's De Humani Corporis Fabrica lies not so much in the marvellous dissections and illustrations, but in the understanding that this one man virtually invented human anatomy.¹ True, Leonardo da Vinci had undertaken human dissections with great difficulties from church and state; but though important, they were not comprehensive. De Fabrica was published in 1543 in seven books written in Latin. Not only is it a singular, original piece of scholarship,² but it is also a work of beauty, bearing fine woodcuts and copperplate illustrations of his dissections— probably the creations of Jan Stephan Kalkar, a student of Titian.³ For many years Dr William Richardon, a classicist, and Professor John Carman, an anatomist, have been collaborating on the first full translation of De Fabrica into English. Book I was published in 1998 and Book II in 1999. Now we have Books III and IV.⁴

Vesalius was highly critical of, and at times rude about, the publications of his contemporaries. He took issue with Galen's sacrosanct authority on several matters in a 1540 translation into Latin of his works on nerves, arteries, veins and dissection. Vesalius's Books III and IV indicate many discrepancies between the received wisdom, descended from Galen almost unchanged, and the observations of his own detailed, laborious dissections. He denounced the unquestioning acceptance of Galenic doctrine, because Galen's descriptions were founded mainly on observations made not in man but in oxen and sheep. In his time, arteries, veins and nerves were collectively regarded as vessels: Greek angeia, Latin uasa or uascula—the 'threesome of vessels'. In an informative preface Richardson discloses that this concept troubled Vesalius, because originally he failed to find a lumen in nerves (vide infra) whereas arteries and veins contained hollow channels; however, he continued to use this traditional grouping, and his notions of physiology followed historical precepts.

A crucial example was the ancient word spirit, spiritus, translated from the Greek pneuma, used by Galen and meaning air in motion. The pneuma according to Erasistratus was inhaled into the lungs and then to the heart's left ventricle where it was changed into the vital spirit distributed by the aorta. The Erasistratean view was that arteries contain the vital spirit, veins blood, and nerves the animal spirit, and this is one of the puzzling aspects of Vesalius's account. He names the pulmonary artery or trunk vena arterialis and the pulmonary vein arteria venalis. But in chapter 15 of Book III he explains that this contradiction arises in relation to the function rather than the structure of these vessels. Another issue was Galen's account of the rete mirabile, essential to Galen's concepts of the brain's circulation. Vesalius set out to demonstrate the rete at his public dissections:

'I was so keen not to gain the reputation of having been unable to find the plexus... that I imposed upon my audience by demonstrating from a sheep's head something I had never found in a human one.'

As the anatomist Carman points out, this typifies the transition of Vesalius from impressionable student to rigorous critic.

Carman says the modern anatomist will have difficulties in assessing Vesalius's work on nerves and vessels since nomenclature was so limited. Vesalius's text shows that only the largest trunks of arteries and veins had names, and he describes (but has no names for) smaller peripheral branches: he uses terms such as 'the vein of the upper arm, the second branch of the vein of the upper arm, and the common vein.' The text and illustrations make this plain. We have eight cervical nerve roots, Vesalius had seven, so that our C8 equates with Vesalius's T1. Likewise our T12 is Vesalius's L1. Though De Fabrica describes the cranial nerves, his numbering does not correspond to modern conventions. The veins, for Vesalius, were distributing vessels with branches, not a system of tributaries (Figure 1). He had a limited number of human bodies in which to make observations so that the many common anatomical variations were underestimated. But the astonishing detail of his work is shown in a huge illustration of 'all the veins and arteries' of the body, inserted as a superb gatefold, with its index of 170 items, at the end of Book III. Book IV describes olfaction plus the seven cranial nerves known in Vesalius's time. Then follow illustrated chapters on the spinal cord, cervical, thoracic and lumbosacral nerves and their branches in the limbs.

Figure 1.

'The hollow vein laid bare and freed from all other parts'

The text contains marginal references, which the authors lucidly tabulate and explain in modern nomenclature throughout the books. They refer to annotated illustrations with lengthy explanatory indices (captions). The high quality of the translation is evident. The correlation with modern terminology must have posed great difficulties for reasons explained. Many excellent translators' notes clarify Vesalius's descriptions and nomenclature. For example, Vesalius states that the origin of the coronary arteries stands behind the small membranes; the translators explain: these small membranes were not called valves until after Vesalius's time. A paragraph on p. 184, headed 'Do the Optic Nerves have a Channel?', illustrates the clarity of the translation, and an example of optic atrophy gives the flavour of Vesalius's methods:

'Among the other nerves of the body these alone are said to be perforated by a perceptible channel; and this is why the Greeks (especially Herophilus and Eudemus) called them poroi optikoi (“optic channels”). I can state that I have never found such a channel, though I have operated with this sole end in view on the optic nerves of living dogs and other large animals and even on the still warm head of a man who had been beheaded: I made a very careful examination of his nerves barely fifteen minutes after his execution, carefully keeping them warm in hot water. I found no such channel anywhere throughout the entire length of the nerve, nor anywhere in the mutual congress of the nerves; and yet I should have found a very large one there, seeing that the reason for the congress, according to Galen, is so that single things should not look double to us...

I shall here make mention of two things that I have noticed.... awoman.... her right eye had withered at the onset of maturity leaving the left unaffected. In the woman the right optic nerve was much thinner than the left over its entire length not only at the point of insertion into the eye but also at the origin and on the right side of the congress of the nerves. The right nerve was not only thin but harder and redder....'

To those fascinated by medical history or those who may wonder how current anatomy was founded and how Vesalius interpreted his observations, this sumptuously produced translation is an unparalleled contribution that does great credit both to its authors and to its publisher.