John Heaviside. Mezzotint by R. Earlom, 1803, after J. Zoffany.

Heaviside is holding the dried preserved heart of Philip Kendal, a tallow chandler of Denmark Street, London, who died in the early 1780s. Kendal's case was described by the surgeon and anatomist Henry Watson-- a later-forgotten anatomist of late 18th-century London-- in Medical communications (Society for Promoting Medical Knowledge), 1784, vol. 1, p. 228, with an engraving of the heart. Watson kept the preserved heart in his anatomical museum, a collection that was probably a rival to those of his better known counterparts William and John Hunter. When he died, Watson's collection was purchased by Heaviside, a surgeon who laid claim to anatomical knowledge by buying the collections of anatomical preparations built up by others. Heaviside later opened his own anatomical museum to the public, and even provided refreshments to visitors. The portrait of Heaviside pointing to the heart is a statement of ownership - and by extension, of medical authority over patients' bodies, a defining feature of anatomy-based medicine

An engraving of Kendal's heart was also included in Matthew Baillie's A series of engravings, accompanied with explanations, which are intended to illustrate the morbid anatomy of some of the most important parts of the human body, London 1799-1803, plate 5, the book being one of the first (if not the first) illustrated atlases of pathology published in England. The heart is described thus by Baillie, loc. cit.: "The object of this plate is to represent a large ossification upon the surface of the heart. Ossification of the pericardium, or of the muscular structure of the heart, occurs very rarely ... the extent of the ossification ... was so great as to prevent the full degree of contraction ... From Mr Heaviside's museum"

London (53 Fleet Street) : Published ... by Rob.t Laurie and Ja.s Whittle, 25 Aug.t 1803.

1 print : mezzotint

John Heaviside Esq.r Surgeon extraordinary to the King, F.R.S., F.A.S. &c. From an original picture in the possession of J. Doratt Esq.r J. Zoffany Esq.r R.A. pinx.t Rich.d Earlom sculp.t

R. Burgess, Portraits of doctors & scientists in the Wellcome Institute, London 1973, no. 1332.4

Wellcome Collection 4083i