L0003618 Portrait of Erasmus Darwin
Portrait of Erasmus Darwin. Engraving by Alpin and Alpin after J. Wright. Credit: Wellcome Library, London. Wellcome images images@wellcome.ac.uk      http://wellcomeimages.org Available under Creative Commons Attribution only licence CC BY 4.0 http://creativecommons.org/licenses/by/4.0/

We end the series with another Darwin, this time Charles’ grandfather: physician, natural philosopher, inventor and poet Erasmus Darwin, and his ‘medico-philosophical’ work, Zoonomia.

Erasmus Darwin (1731-1802) became well known for his medical work and healing and ran a successful medical practice in Lichfield between 1756 and 1781 before going on to work in Derby. A man of varied interests, as well as treating patients Darwin was a keen inventor, and he studied chemistry, geology and botany. His absorption into the field of botany led to the construction of his own botanic garden and translations of works of Linnaeus. Darwin’s own poetic work, The loves of plants, was published anonymously in 1789 and centred on the Linnaean classification of plants. This was reprinted in 1791 as part 2 of The Botanic Garden, along with another poetic work, The Economy of Vegetation. An innovator in science and industry, Darwin was also a founding member of the Lunar Society of Birmingham.

Erasmus Darwin referred to his Zoonomia as his ‘medico-philosophical’ work. According to the Preface, it aimed “to reduce the facts belonging to animal life into classes, orders, genera, and species; and by comparing them with each other, to unravel the theory of diseases.” Representative of the theory that classification produces knowledge, the work also aimed to form a basis for good medical practice.

In Zoonomia he categorised the laws of animal motion as:
irritative (from the stimulation of organs of sense and muscular fibres from external sources)
sensitive (caused by pleasure or pain)
voluntary (caused by desire or aversion)
associative (when diseases of one organ or system caused other problems)

The first volume was published in 1794 (STORE 74:1). This was followed in 1796 by a second volume (STORE 74:2) containing a catalogue of diseases, divided into the classes of ‘irritation’, ‘sensation’, ‘volition’ and ‘association’. Also included was a materia medica of substances for medical treatment of these diseases. The Whipple’s copy of Volume I contains a typed note explaining that this Dublin edition was published simultaneously with the first London edition. Also inside the front cover is the bookplate of a Robert Wilmot, perhaps connected to the Robert Wilmot whose case is included under diseases of association and the suffering of gout in Volume II.


Particularly interesting in the Zoonomia are Darwin’s optical experiments on eye movements and afterimages, or ‘ocular spectra’. Volume I begins with studies of motion, including motions of the retina, demonstrated by experiments. These include the following examples on a tadpole shaped spot:

and different coloured circles of silk:

The Whipple’s 1794 edition has been hand painted, and the 3rd edition of 1801 was also hand coloured (STORE 170:19).

Included at the end of Volume I is a paper ‘On the ocular spectra of light and colours’ by Dr. R.W. Darwin of Shrewsbury. This was Robert Waring, Charles Darwin’s father. Born in 1766, he became a successful physician and set up his own medical practice in Shrewsbury. The paper included further optical experiments, including this one:

STORE 170:19

Zoonomia is also significant for the section ‘Of Generation’ where Darwin presented his theories, including that all warm-blooded animals may have “arisen from one living filament”, and that generation involved continuous development and the passing on of capacities through living creatures. He noted that many species have adapted in different ways and for different reasons. This section was revised and expanded for the 4 volume 3rd edition (STORE 170:19-22). In it, Erasmus anticipated many of the later arguments concerning adaptation and reproduction and Charles Darwin’s exposure to these ideas may have played a part in his own theory of evolution. The Whipple’s copy of the 3rd edition came from the collection of marine biologist George Parker Bidder.

Maureen McNeil, ‘Darwin, Erasmus (1731–1802)’, Oxford Dictionary of National Biography, Oxford University Press, 2004; online edn, Sept 2013 [http://www.oxforddnb.com/view/article/7177, accessed 21 Dec 2016]
Nicholas J. Wade (2010) ‘The Darwins and Wells: From Revolution to Evolution’, Journal of the History of the Neurosciences, 19:2, pp.85-104
Nicholas J. Wade (2010) ‘Pioneers of eye movement research’ i-Perception, volume 1, pp.33 – 68
http://www.microfluidics.ca/zoonomia-long.html [accessed 21 Dec 2016]