Tracking the British agricultural revolution through the isotopic analysis of dated parchment

Abstract

Between the sixteenth and nineteenth century, British agriculture underwent a ‘revolutionary’ transformation. Yet despite over a century of research and the recognised centrality of agricultural developments to industrialisation and population growth, the character or chronology of any ‘revolution’ during this period remains contentious. Enquiry has been hampered by the fragmented and locally specific nature of historic accounts and the broad dating of early-modern zooarchaeological assemblages. To address this, we conducted stable isotope analysis on 658 legal documents written on sheepskin parchment; a unique biological resource that records the day, month and year of use (AD 1499 to 1969). We find these provide a high temporal resolution analysis of changing agricultural practices and episodes of disease. Most significantly, they suggest that if an ‘Agricultural Revolution’ occurred in livestock management, it did so from the mid-nineteenth century, in the aftermath of the Napoleonic Wars.

North and South: Exploring isotopic analysis of bone carbonates and collagen to understand post‐medieval diets in London and northern England

“…With the exception of three pigs, all animals exhibited 𝛿 13 C coll , 𝛿 13 C carb and 𝛿 15 N values consistent with livestock raised in the British Isles grazing on C 3 forage and fodder crops. The substantial range in cattle and sheep 𝛿 15 N values (5.4‰ and 7.2‰, respectively) likely reflects the large geographical range from which livestock were drawn to feed the burgeoning industrial towns (Scola, 1992) and the diversity in environmental conditions and land management practices in these areas, particularly the intensity of manuring (Doherty et al, 2023). Elevated 𝛿 15 N values in some pigs and domestic fowl indicate a diet with a component of animal protein, typical of omnivores consuming human refuse (Halley & Rosvold, 2014; Hammond & O'Connor, 2013).…”

“…In cases where there are elevated δ 13 C and δ 15 N values (corresponding to Functions 1 and 2 respectively in this case) in children under the age of 2, this may be interpreted to have resulted from breastfeeding (Beaumont et al, 2015), therefore all non-adults were excluded from the overall interpretation of a C 4 diet. Around to feed the burgeoning industrial towns (Scola, 1992) and the diversity in environmental conditions and land management practices in these areas, particularly the intensity of manuring (Doherty et al, 2023).…”

Experimental Observations on Processing Leather, Skin, and Parchment for Radiocarbon Dating

“…Skin-based samples should have high gelatin yields because most of the sample weight is composed of collagen. While bone gelatin yields below 2-4% indicate that the bone gelatin is degraded(DeNiro and Weiner 1988; van Klinken 1999), previous tests of gelatinizing historical parchment show gelatin yields by mass ranging from 46.7-71.3%(Brock 2013) and 32.4-98.3%(Doherty et al 2023). Experimental results have also shown that contemporary unprocessed skin samples have average gelatin yields of 70%, slightly higher than the average 63% yield of parchment(Doherty et al 2021).…”