COP26 – Part 2: Latent Heat at the University Library

This is the second of a pair of blogs exploring environmental aspects of the study of borrowing records from historic Scottish libraries, in recognition of the globally significant COP26 conference taking place in Glasgow in November 2021.

In April 1762, the Regius Professor of the Practice of Medicine at the University of Glasgow, Joseph Black, gave a talk to the university’s ‘Philosophical Club, or Society of Professors and others’.[1] In the period leading up to this presentation, he had undertaken a series of experiments to confirm a hypothesis he had been developing since the later 1750s. Building on the work of Gabriel Daniel Fahrenheit and others, plus his own observations about the curiously slow melting of ice, Black had demonstrated the existence of what he called ‘latent heat’.

Engraving of Black from the 1807 Philadelphia edition of Lectures on the Elements of Chemistry, vol. 1.

Having combined together specific quantities of ice and warm water, Black explained: ‘The mixture should have been 85 degrees warmer than melting ice; but it was found only 21 degrees warmer. Therefore a quantity of heat has disappeared, which, if it had remained in a sensible state, would have made the whole mixture and glass warmer by 65 degrees than they were actually found to be. But this quantity of heat would be sufficient for increasing, by 143 degrees, the heat of a quantity of water, equal in weight to the ice alone. It was, however, absorbed by the ice, without in the least increasing its sensible heat.’[2]

The 1797 third edition of the Encyclopædia Britannica glossed this revelation in the following terms: ‘Dr Black is of opinion that heat, which he seems to make synonymous with fire, exists in two different states; in one of which it affects our senses and the thermometer, in the other it does not. The former therefore he calls sensible heat, the latter latent heat. On these principles he gives the only satisfactory explanation of the phenomena of evaporation and fluidity that has yet appeared.’


Laboratory apparatus and equipment – plates from Black’s Lectures on the Elements of Chemistry, vol. 1.

As ice melts into water, Black realised, it absorbs heat without a corresponding change in temperature. This ‘latent’ heat is released when it freezes again into ice. The same process, Black deduced, takes place when water is vapourised into steam and then condensed back into water: an absorption of thermal energy in the form of latent heat, and then its release.

When John Robison came to publish Black’s lectures in 1803, he made a very explicit link between this research and the improvements to Newcomen’s steam engine made by the man he called Black’s ‘most illustrious pupil’, James Watt. In a prefatory dedication to Watt, Robison declaimed: ‘Surely nothing in modern times has made such an addition to the power of man as you have done by your improvements on the steam engine, which you profess to owe to the instructions and information you received from Dr. Black’. Watt, in fact, would deny such a causal link, though he ‘always acknowledged his obligations to Black, particularly for the knowledge of the doctrine of latent heat’, emphasising instead his own experiments as the essential basis for his breakthrough.[4]

‘Watt’s steam engine’, George Arents Collection, The New York Public Library Digital Collections.

Black’s work on thermodynamics and Watt’s practical application of these same laws in his incredibly consequential improved steam engine again points us to the culture of inquiry – and ‘improvement’ – discussed in Part 1 at the University of Glasgow in the early 1760s. Black’s chemistry, Adam Smith’s political economy and Watt’s technical innovations are some of the most well-known outcomes of this milieu.

In what ways, then, might the university’s borrowing registers speak to this history? The first thing to remark is that Watt himself does not appear in the Glasgow registers – bear in mind that he was attached to the institution as an instrument maker, rather than as a student or member of the professorial staff. Both Black and Smith do appear, however, the latter in a run of fifty-three borrowings across 1754 to 1762 that are a fascinating insight into his reading.

At the end of this period, across 1762-1763, Smith would deliver his famous Lectures on Jurisprudence at Glasgow. These lectures are a precedent for ideas in the Wealth of Nations but also, in their own right, a foundational text for the stadial model of history now closely associated with the Scottish Enlightenment. Smith is credited with having coined the specific ‘four stages’ model of civilizational development here. As he explains in his lectures, ‘There are four distinct states which mankind pass thro:––1st, the Age of Hunters; 2dly, the Age of Shepherds; 3dly, the Age of Agriculture; and 4thly, the Age of Commerce.’[5] This explicitly teleological view of human society, which posits modern commerce as the logical outcome of a developmental process rather than one option among alternatives, remains foundational to the way we think about cultural difference – the late David Graeber’s cowritten The Dawn of Everything (2021), for example, represents an ongoing effort to reckon with it.[6] It is certainly indicative of a Whiggish confidence in ‘improvement’ writ large that accompanied ­the technological advances of the eighteenth century, enabling them to be represented as steps on a civilizational ladder.

While Smith was preparing this thinking, we can note a strong emphasis in his borrowings from the university library on legal texts such as Edward Coke’s Institutes of the Laws of England (1664-1670, borrowed 1754), Thomas Craig’s Jus Feudale (1732, borrowed 1755), Matthew Bacon’s New Abridgment of the Law (1736-1766, borrowed July 1762) and William Dugdale’s Origines Juridiciales (1671, borrowed August 1762). Equally, Smith’s interest in the popular genres of history and travel – for example, James Tyrell’s General History of England (1698-1704, borrowed 1755), Jean Baptiste Louis Crevier’s Histoire des Empereurs Romains (1749-1756, borrowed 1758), George Anson’s Voyage Round the World (1748, borrowed 1758) and Richard Pococke’s Description of the East (1743-1745, borrowed 1760) – might also be constituted within an expansive, proto-sociological project of outlining the essential logic of civilization, as it was supposed to ‘improve’ from hunter-gathering through to commercial stages.

A selection of Adam Smith’s borrowings from Glasgow University Library, ledger 1, page 7r.

More generally, and keeping the focus on the years immediately surrounding Watt’s invention of the separate condenser, we have two borrowing registers to consider: a volume of professorial borrowings covering 1751-1765 and one of student borrowings covering 1760-1765. In the professorial register, the two most frequently borrowed texts are the proceedings of the French royal academies of the arts and sciences: Histoire de l’Académie Royale des inscriptions et belles lettres (1717-1780, borrowed fourteen times) and Histoire de l’Académie Royale des sciences avec les mémoires de mathématique et physique (1666-1789, borrowed ten times). As this suggests, for all the distinctive regional experience of Glasgow as discussed in Part 1, the ‘improving’ intellectual culture of the university was deeply bound into international networks. Joseph Black, for example, can be seen returning to volumes of l’Académie Royale des sciences in the years preceding his experimental proof of latent heat.

The early 1760s student register, for its part, is typical of what we are seeing with student borrowings across the Scottish universities in the middle decades of the eighteenth century, since is dominated by multi-volume historical surveys: An Universal History, from the earliest account of time (1747-1754, borrowed fifty-six times), Charles Rollin’s The Ancient History of the Egyptians, Carthaginians, Assyrians, Babylonians, Medes and Persians, Macedonians, and Greeks (1734-1739, borrowed 55 times) and Paul de Rapin-Thoyras’s History of England (1725-1746, borrowed 51 times). Again these ambitious, synoptic accounts of the past sit naturally within the civilizational project of the eighteenth century, although as Clifford Siskin has recently argued, the Enlightenment systemisation of knowledge was always internally contested ­– certainly the improving optimism of the Scottish contribution was accompanied by a critique of polite decay, luxury and potential regression developed most famously by Adam Ferguson.[7]

The are other, more individual borrowings in the Glasgow library records that might be constituted within a prehistory of environmentalism ­– such as Carl Linnaeus’s Hortus Cliffortianus Plantas Exhibens (1737) or Phillip Miller’s The Gardener’s Dictionary (1733-1739). Equally, the taxonomic natural history of the era would be granted further shape in Glasgow’s Hunterian Library, from which we have surviving borrowing records covering a later period (1808-1852). In broad terms, however, Fredrik Albritton Jonsson and Eric Gidal have both identified the Scottish experience of improvement in the second half of the eighteenth century as a crucible for an emerging consciousness of natural limits and destabilising change that would become modern environmentalism.[8] As I have explored briefly here, the Glasgow borrowings can thus be situated within a wider culture of improvement that produced the carbon age as one of its primary consequences, even where the borrowings are not of technical manuals or natural history.

It would hardly be appropriate to end this blog without noting the pivotal role played by Joseph Black in the discovery of carbon dioxide (which he described as ‘fixed air’) – of course the greenhouse gas that is now causing a devastating global warming effect as a result of anthropogenic emissions into the atmosphere.[9] The point of the foregoing is not, to be clear, to dissolve the complex life of the eighteenth-century university, or indeed the multifaceted keyword ‘improvement’, into a single historical trajectory; far less is it to assign blame to the individuals I have discussed for the consequences of the energy transformations in the second half of the eighteenth century. Rather, the purpose of this blog has been to sketch out a wider, multi- and pre-disciplinary milieu without which Watt’s steam engine and all it has meant for the world would not have been possible.

Detail from Charles Ross, ‘A map of the shire of Lanark’ (1773). Reproduced with the permission of the National Library of Scotland.

[1] Joseph Black, Lectures on the Elements of Chemistry [1803], ed. John Robison, 3 vols (Philadelphia: Matthew Carey, 1807): vol. 1, 120.

[2] Ibid.

[3] ‘Chemistry’, Encyclopædia Britannica, 3rd edn, 18 vols (Edinburgh: A. Bell and C. Macfarquhar, 1797), vol. 4, 379.

[4] Black, Lectures on the Elements of Chemistry, vol. 1, iii; and see J. R. Partington, ‘Joseph Black’s “Lectures on the Elements of Chemistry”, Chymia, 6 (1960): 27-67, (28). On the dating around the discovery of latent heat, including the possible prior claim of Jean André Deluc, see Lectures on the Elements of Chemistry, vol. 1, 357-70; and Stefan Emeis, ‘The discovery of latent hear 250 years ago’, Meteorologische Zeitschrift, 13.4 (August 2004): 329-33.

[5] Adam Smith, Lectures on Jurisprudence, ed. R L. Meek, D. D. Raphael and P. G. Stein (Oxford: Oxford University Press, 1978), 14.

[6] David Graeber and David Wengrow, The Dawn of Everything: A New History of Humanity (London: Allen Lane, 2021).

[7] Clifford Siskin, System: The Shaping of Modern Knowledge (Cambridge, Mass.: MIT Press, 2016); Adam Ferguson, An Essay on the History of Civil Society (London: A. Miller & T. Caddel; Edinburgh: A. Kincaid & J. Bell, 1767).

[8] Fredrik Albritton Jonsson, Enlightenment’s Frontier: The Scottish Highlands and the Origins of Environmentalism (New Haven: Yale University Press, 2013); Eric Gidal, Ossianic Unconformities: Bardic Poetry in the Industrial Age (Charlottesville: University of Virginia Press, 2015).

[9] See, for example, Black, Lectures on the Elements of Chemistry, vol. 2, 215.