the men of nelson's navy: a comparative stable isotope dietary study of late 18th century and...

The Men of Nelson’s Navy: A Comparative StableIsotope Dietary Study of Late 18th Century and Early19th Century Servicemen From Royal Naval HospitalBurial Grounds at Plymouth and Gosport, England

Patrick Roberts,1 Sam Weston,1 Bastien Wild,1,2 Ceridwen Boston,1 Peter Ditchfield,1

Andrew J. Shortland,3 and A. Mark Pollard1*

1Research Laboratory for Archaeology and the History of Art, School of Archaeology, Dyson Perrins Building,South Parks Road, Oxford OX1 3QY, UK2Department de Chimie, Ecole Normale Superieure de Paris, 24 Rue Lhomond, 75005 Paris3Centre for Archaeological and Forensic Analysis, Department of Engineering and Applied Science,Cranfield University, Bedfordshire MK43 0AL, UK

KEY WORDS stable isotopes; bone; Royal Navy; Haslar; Plymouth

ABSTRACT We present stable isotopic analyses of col-lagen from 80 servicemen excavated from the late 18th/early 19th century naval hospitals at Plymouth (50) andHaslar, Gosport (30) in southern England. Historicalrecords suggest that, the diets of these two populationsshould be essentially identical. While d15N of the rib colla-gen confirmed that naval servicemen were relatively well-catered for in terms of meat allowance (Plymouth averaged15N 5 11.1%, Gosport 5 11.9%), stable carbon isotopeanalysis produced average values for the two assemb-lages, which were significantly different (Plymouth aver-age d13C 5 218.8%, Gosport 5 220.0%). We postulatethat these differences stem from divergent naval postings,with a greater proportion of Plymouth individuals servingin areas that entailed a greater input of C4 foodstuffs. By

comparison with published data from approximately con-temporary burials at Snake Hill, Ontario, Canada andChesapeake Bay, Virginia, we suggest that this area is theeast coast of North America. For 15 of the 30 individualsfrom Gosport, we have data on ribs, femur, and dentinefrom the same skeleton, which appear to show that theycame from a variety of locations in their preadolescence,but converged in dietary terms onto a ‘‘naval average,’’which is consistent with historical evidence for recruit-ment patterns into the Navy at the time. By comparisonwith published data from skeletons recovered from thewreck of the Mary Rose (sank 1545), we conclude that thisnaval diet was virtually unchanged from the 16th centuryto the end of the 18th century. Am J Phys Anthropol000:000–000, 2012. VVC 2012 Wiley Periodicals, Inc.

The study of diet is of central importance in botharchaeological and historical contexts, allowing insightsinto social classification, exchange networks, and geo-graphical mobility, as well as knowledge of the nutri-tional state and general health of a population. Archaeo-logically, dietary studies can be undertaken using anumber of different approaches (primarily using directevidence of food remains or isotopic analysis of bone col-lagen), but are usually only capable of general levels ofinterpretation (typically either averages across a popula-tion, or long-term time averages for an individual).Written records, if reliable, provide much more specificinformation on what was eaten, when, and by whom.Therefore, where possible, it would be useful to overlapthese two very different methodological approaches, toprovide a more complete dietary picture, to the mutualbenefit of both disciplines. The osteological and isotopicstudy of British Royal Navy (RN) skeletons of the late18th century and early 19th centuries, combined withthe rich historical documentation of the Navy of thisperiod, affords just such an opportunity.We have applied stable carbon and nitrogen isotope

analyses to the bulk bone collagen from the remains oflate 18th century and early 19th century British RN sea-men and marines from naval hospital burial grounds atPlymouth and Haslar, Gosport on the south coast of Eng-

land (Fig. 1) excavated by Exeter Archaeology and Cran-field University respectively. In the late 18th and early19th centuries, Britain was almost constantly at war, andthe RN was central to the maintenance of national secu-rity and the promotion of Britain’s political and mercantileaspirations abroad (Rodger, 2004). In the late 18th cen-tury, the RN employed �70,000 seamen and marines. Bythe height of the Napoleonic Wars (c. 1803–1815), this fig-ure had doubled (Clowes, 1900). Feeding so many menwas a huge logistical challenge, particularly as long dis-tance seafaring requires the preservation of on-boardrations over long periods. The victualing of British RN

Additional Supporting Information may be found in the onlineversion of this article.

*Correspondence to: A. Mark Pollard, University of Oxford,Research Laboratory for Archaeology and the History of Art, DysonPerrins Building, South Parks Road, Oxford, Oxfordshire OX1 3QY,United Kingdom. E-mail: [email protected]

Received 22 September 2011; accepted 21 December 2011

DOI 10.1002/ajpa.22019Published online in Wiley Online Library

(wileyonlinelibrary.com).

VVC 2012 WILEY PERIODICALS, INC.

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 000:000–000 (2012)

ships had been strictly controlled since at least the time ofHenry VIII (AD 1491–1547). Based on captain’s logs of1757–1762, Rodger (1986; 352) determined that on aver-age naval ships spent 43% of the year at sea and 57% inport (although the latter would also include time at anchorand therefore still subject to naval regulation). Slope’s(2006) study of three frigates during the Revolutionaryand Napoleonic Wars reveals that sea time increased onlyslightly to 55% over the course of the 18th and early 19thcenturies. Thus, the sample discussed in this article com-prised a relatively highly controlled group of individuals,some of whom spent large portions of their life at sea andconsequently survived on a very regulated and well-docu-mented diet of officially distributed rations.The objectives of this study were to:

1. Investigate whether the stable isotopic analysis ofbone collagen from 18th century and early 19th cen-tury sailors correlated with the historical informationon diet in the RN.

2. Use the isotopic differences between elements of theskeleton in a single individual to look for dietarychange through a person’s lifetime.

3. Investigate the supposed homogeneity of the navaldiet across two contemporary populations.

4. Compare these isotopic data with data published on

18 individuals from the Mary Rose, a 16th century

royal flagship that sank just outside Portsmouth har-

bor in 1545 (Bell et al., 2009), to investigate the chro-

nological homogeneity of British naval diets.

HISTORICAL CONTEXT

While this study is breaking new ground in the appli-cation of stable isotope dietary methods to late 18th cen-tury and early 19th century British naval history, histor-ical research into this period is extensive, includingdetailed studies of the records of naval diets (e.g., Wattet al., 1981; Macdonald, 2006). Such work has providedin-depth insights into RN organization and the life ofthe men at sea, and indicates the potential nuancesinvolved in reconstructing 18th century naval diet froman isotopic study of the human remains.In the 18th century, British RN provisioning was

under the control of the Victualling Board (Macdonald,2010), which imposed strict limitations on what food-stuffs could be included in official rations. Food on boardship had to be preserved for months, sometimes years,but preservation was expensive and often unreliable[although the evidence is that recorded spoilage at seawas minimal, \1% of pork and beef was condemned asspoilt when opened at sea (Rodger, 1986; 84)]. Meat wasprocessed at the Victualling Yards at Portsmouth andPlymouth, by salting. In addition, many ships carriedliving livestock on board, for slaughter later in a voyage(Rodger, 1986; 69–71). Table 1 shows the individual

Fig. 1. Site locations.

TABLE 1. The food rations per man issued by the Victualling Board in the mid-18th century (Rodger, 1986; 83)

Bread Beer Beef Pork Pease Oatmeal Butter Cheese

Sunday 1 lb 1 gal 1 lb 0.5 ptMonday 1 lb 1 gal 1 pt 2 oz 4 ozTuesday 1 lb 1 gal 2 lbsWednesday 1 lb 1 gal 0.5 pt 1 pt 2 oz 4 ozThursday 1 lb 1 gal 1 lb 0.5 ptFriday 1 lb 1 gal 0.5 pt 1 pt 2 oz 4 ozSaturday 1 lb 1 gal 2 lbs

2 P. ROBERTS ET AL.

American Journal of Physical Anthropology

weekly rations for a British seaman in the mid-18th cen-tury (Rodger, 1986; 83). This diet continued largelyunchanged from the late 17th century, if not earlier,until canning was accepted as a means of preservationin 1843 (Macdonald, 2006). The bread was wheatenloaves (‘‘soft tack’’) when in port and ship’s biscuits ofbaked flour and water (‘‘hard tack’’) when at sea. Inaddition to these rations, the Board supplied flour, oat-meal, suet, cheese, raisins, dried peas, vinegar, oil, orbutter (depending on a ship’s destination), beer, andsometimes stockfish (salted and dried cod). Rodger(1986; 83) states that between 1750 and 1757 the Vict-ualling Board provided 4,498,486 lbs of beef, 6,734,261lbs of pork, and 166,943 lbs of stockfish (ratio by weight39% beef, 59% pork, 1.5% stockfish). Stockfish had orig-inally been part of the 17th century naval diet stipulatedby Samuel Pepys (as King’s Secretary for the affairs ofthe Admiralty), but was officially dropped by 1733because of its tendency to rot (Macdonald, 2006). Itwould appear that it continued to be supplied in smallquantities well into the 18th century. Despite a dearth offresh vegetables and fruit, the diet of the 18th centuryRN was plentiful and of relatively high quality comparedto that of working class civilian contemporaries, which iscommonly held to have consisted of bread, cheese, beer,and meat once a week (Macdonald, 2006; 11). Meat for 4days a week would certainly have been considered aprivilege by a large section of society at the time.This historical information has two implications when

considering the stable isotope analysis. First, as Table 1shows, the plant input into the diet was dominated bywheat-based bread or biscuit, barley (as beer), and oat-meal. All of these cereals photosynthesize using the C3

pathway, and there are no obvious sources of C4 protein(see below), which has the implication that the diet (bothprotein and starches) was relatively monoisotopic anddepleted in 13C, resulting in an expected value of�221% for the d13C values in the consumer tissues(e.g., Schoeninger and Moore, 1992; 260). Second, theprovision of large quantities of meat for four times aweek leads to the expectation of elevated d15N bulk bonecollagen values, due to the relatively high protein input,using the ‘‘standard model’’ of nitrogen trophic levels inhumans, this would be around d15N 5 10 2 12%(Hedges and Reynard, 2007; 1246). Furthermore,although stockfish appears to have been part of theration, the relative paucity of fish (and marine protein ingeneral) is unlikely to lead to a significant elevation ofboth d13C and d15N values due to the consumption of ma-rine protein (Richards and Hedges, 1999; Fig. 2). This

detailed historical context thus provides a benchmark forthe interpretation of the stable isotope data whichshould be, theoretically, consistent across individualsirrespective of where they sailed. Moreover, as discussedabove, the diet of a British sailor may be expected tohave differed minimally over a period of at least 200years, prior to the introduction of modern long-life food-stuffs in the mid-19th century.However, against this straightforward picture must be

placed other historical studies, which emphasize nuancesin this pattern. Indeed, Rodger has claimed that one of the‘‘banes of naval social history is the assumption, still wide-spread in the teeth of all probability, that nothing everchanged’’ (Rodger, 1986: 12). In terms of isotopic studies,the human subjects themselves may not provide a com-pletely homogeneous group. On deck were not only sea-men, but also marines. The former were largely recruitedfrom the merchant navy from ships and ports around theworld, and were selected for their seamanship rather thantheir nationality (Lambert, 2004). There is, therefore, nonecessity for these men to be ‘‘British’’ either in terms ofgeographical origin or of a single dietary background dur-ing their formative years. Many were boys, who began lifein the RN from as early as 10-years-old (Lambert, 2004).Unlike seamen, marines were primarily recruited fromthe rural laboring communities of Britain, although someforeigners also entered the RN in this group. In peace-time, all naval recruits were volunteers. During wartime,however, the navy had a legal right to obtain men throughforced impressment and quotas, as well as by volunteering(Lambert, 2002).When considering a dietary isotopic study of naval

assemblages, it is therefore crucial to bear these caveats inmind. Although some men may have been in the navy sub-sisting on naval rations from early adolescence, leading toa group with relatively homogeneous dietary signals inadulthood, others could well have joined from very differentdietary backgrounds later in life. It is thus of interest touse the differential rates of collagen turnover within a sin-gle skeleton to compare adolescent with adult diets in orderto reconstruct individual life histories (Sealy et al., 1995).Although post-adolescent diets have less impact on the col-lagen dietary signal (even in femora: Hedges et al., 2007),the longer a person had been in the navy, the more likely itis that he will show the ‘‘naval diet’’ signature. Individualswho came from a different dietary background (e.g., some-body recruited on the east coast of North America, wheremaize (a C4 cultigen) is likely to induce a very differentd13C signal), may be detectable by a marked difference indietary isotopes between teeth (reflecting early life) andbone (indicative of later life).A second nuance is in terms of the postulated naval

diet itself. Table 1 implies a stable, monotonous diet forthe servicemen. However, there is a mass of historical in-formation to suggest that, to differing extents, local pro-duce was used to substitute part or all of the standar-dized sea diet when in port (Lavery, 1998). That said,the supplementing of one food for another was itselftightly prescribed by the Victualling Board (Rodger,2004). A captain had to pay for the food substitutes outof his own pocket, to be reimbursed by the Board uponhis return. However, if there was any dispute about thereplacement food, he could be personally out of pocket.The potential of this scenario was likely to restrict howcreative captains were with local dietary substitutions(Macdonald, 2006). In addition, less affluent captainsmay not have had the capital to finance such schemes.

Fig. 2. Comparison of isotopic values for ribs, femora, anddentine from Haslar, Gosport.

3THE MEN OF NELSON’S NAVY


Local produce was also bartered or purchased by themen themselves for their personal consumption (Rodger,1986).

ARCHAEOLOGICAL CONTEXT

The two skeletal assemblages used in this study wereexcavated from the earlier of the burial grounds associ-ated with the Royal Hospitals at Plymouth (1762–1824)and Haslar, Gosport, near Portsmouth (1753–1826),founded by the RN in response to the pressing problemof high rates of death and desertion of their sick andwounded (Lloyd, 1965). Thus, these burial grounds werein use during the 7 years war (1756–1763), the AmericanWar of Independence (1775–1782), the war with theFrench Republic (1793–1801), the Napoleonic Wars(1802–1815), and the Anglo-American War (1812–1815).Conflict was not confined to European waters, butincluded theaters of operation as wide-ranging as NorthAmerica, the Caribbean, Egypt, South Africa, Mauritius,India, and the Baltic.

Plymouth Hospital (1762–1824)

In 2007, the burials of 170 seamen and marines associ-ated with the Royal Naval Hospital at the Millfields,Stonehouse in Plymouth were excavated at Stray Park,Plymouth, by Exeter Archaeology in advance of redevel-opment (Hodgins and Pamment-Salvatore, 2009). Thesite had been extensively used for burial with consider-able intercutting of graves. Nevertheless, the recoveredskeletal assemblage was in a good state of preservation,with minimal mixing of individuals.Surviving burial records for Stray Park burial ground

for the years 1813–1814 record �421 burials in those 2years. By far the greatest proportion of the recorded bur-ials were those of seamen (73%), followed by marines(25.7%), while cooks, carpenters, and assistant surgeonscomprised the remainder (data from Plymouth and WestDevon Records Office, Stray Park burial register 1813–1814; Bishops Transcripts, microfiche reference 2,237,Plymouth). Assuming that these 2 years are representa-tive of the whole period of use of the burial ground, it isapparent that seamen and marines—the so-called ‘‘low-erdeck’’—comprised the bulk of the assemblage, althoughAmerican and French prisoners-of-war were also be bur-ied here (Pugh, 1972). Given the discussion of worldwidevolunteering and impressments above, of particular in-terest is the inclusion of two American prisoners-of-warin the 1814 burial record, probably casualties of theAnglo-American War of 1812.

Royal Naval Hospital Haslar, Gosport

Following an archaeological evaluation and desk-basedassessment carried out by Oxford Archaeology (2005a,b),Cranfield University undertook an archaeological exca-vation in the Paddock in 2007–2010 (Shortland et al.,2008). As at Plymouth, most individuals were recoveredas fully articulated skeletons in single graves, but therewas far less intersection of graves. Data collated fromGilbert Blane’s (1799) ‘‘Observation on the Diseases ofSeamen,’’ 1756–1764 Death of Seamen Registers(ADM102/377), and 1794–1824 Haslar Hospital Musters(ADM102/273-304) indicate that more than 20,000 sea-men and marines were buried in the hospital grounds.In addition, a small number of American, French, andRussian prisoners-of-war, and military casualties of the

Corruna campaign (1808) were also interred there (Tait,1906).

MATERIALS AND METHODS

We have analyzed 80 rib specimens from adolescentand adult burials excavated from the cemeteries atPlymouth (50) and Gosport (30, but one sample failedand one person was sampled twice). In addition, weobtained data from femora and dental collagen for asmany as possible of the 30 individuals analyzed fromGosport. In total, we have 22 measurements on femora(from 21 individuals), and 25 dentine samples, but 15individuals provided data on all three of these skeletalelements. For three of these individuals, we were alsoable to include other skeletal elements. Supporting Infor-mation Tables S1 and S2 list the samples taken fromPlymouth and Gosport, respectively, along with esti-mated age taken from the preliminary osteological anal-yses by Boston (forthcoming).Samples of up to 5 g of bone were collected from the skel-

etal element of each individual. Removal was achieved byeither taking whole fragments if suitable pieces were avail-able, or by sawing off a fragment with a small circularpower saw. Bone samples were subsequently superficiallycleaned using an air abrasive system with 5 lm aluminumoxide powder, followed by crushing an aliquot of 0.5–1 g ofeach bone. Collagen was then extracted following standardprocedures (Richards and Hedges, 1999). Approximately200 mg of precleaned bone was demineralized in 10 ml ali-quots of 0.5M HCl at 48C until CO2 ceased to be evolved.This required three changes of acid, one for every 48 h. Theresidue was rinsed three times in deionized water and thengelatinized in pH 3 HCl at 758C for 48 h. The resulting so-lution was then filtered, with the supernatant being lyophi-lized in a freeze drier after treatment with liquid nitrogen.Approximately 2.5 mg aliquots of the resulting purified col-lagen samples were then weighed out for analysis into pre-cleaned tin capsules.Tooth dentine samples were taken to provide an indica-

tion of dietary nitrogen and carbon stable isotopes duringthe period of tooth mineralization. Dentine from toothsamples was obtained by sectioning the tooth with a slowspeed diamond saw and then drilling out the dentine thatwas covered by the enamel layer. In some instances, thiswas not practical due to extreme wear or damage to thetooth: in these instances, dentine was removed by drillingupwards from the underside of the tooth between the rootswith care being taken to minimize the amount of cemen-tum contamination within the sample. Collagen was sub-sequently extracted from the dentine by the same methodas used for the bone samples. This procedure wasdesigned to minimize the sampling of secondary dentine,but without dissection it is not possible to eliminate com-pletely the inclusion of secondary dentine from tubules.This has the potential for the inclusion of a small propor-tion of carbon in the sample, which was deposited aftermineralization of the tooth was complete.The samples reported here have been analyzed over a

period of 2 years, using two different instruments: inboth cases, these were Sercon 20/20 Isotope Ratio MassSpectrometers in the Research Laboratory for Archaeol-ogy and the History of Art running in continuous flowmode with a helium carrier gas with a flow rate of �80ml per minute. Samples were combusted on a CarloErba elemental analyzer system using a 2% split of thegases evolved. Isotopic values as well as elemental

4 P. ROBERTS ET AL.


abundances and carbon-to-nitrogen molar ratios werecalibrated against an in-house alanine standard whichitself is routinely measured against international stand-ards whose values are traceable back to the V-PDB(Vienna PeeDee Belemnite) international standard. Fur-ther aliquots of the alanine standard were used to moni-tor and correct for instrumental drift. To determine thereliability of the sampling and measurement procedures,the Plymouth ribs were each run as duplicates and themajority of the Gosport samples in triplicate.The samples were run across 18 batches on two mass

spectrometers. For quality control, we include multiplesamples of the in-house alanine standard in each batch.Replicate analysis of the alanine in-house standard gavethe following results (average of 84 measurements):

d13C ¼ �26:92� 0:20& expected value� 26:9&

d15N ¼ �1:48� 0:37&; expected value� 1:6&

This indicates that the individual values obtained dur-ing the analyses reported here are typically accurate to6 0.20% for d13C and 6 0.37% for d15N. Precisions onindividual samples are calculated from the duplicate ortriplicate measurements, as noted in the tables.

RESULTS AND DISCUSSION

Supporting Information Tables S1 (Plymouth) and S2(Haslar, Gosport) show the values obtained for d13C andd15N on each sample, as calculated from a set of dupli-cate measurements in Supporting Information Table S1,and either duplicate or triplicate in Supporting Informa-tion Table S2 (the number of replicates for each sampleis shown in the final column). For each bone samplereported, the Supporting Information Tables show thecollagen yield from the dissolution of the bone (whereavailable), the average %C and %N in each combustedcollagen sample, and the calculated molar C/N ratio. TheC/N ratio is used here as the primary indicator of colla-gen quality and in this study an individual measurementis rejected if it exceeds 3.6. None of the measurementson the ribs from Plymouth have been rejected, but anumber of the measurements from Gosport wererejected, suggesting that the overall preservation of thebone from Gosport is somewhat worse than at Plymouth.Table 2 shows the average value of percentage collagenyield, %C, %N, C/N molar ratio, d13C, and d15N for theaccepted data from Plymouth ribs and Gosport (Haslar)ribs, femurs, and dentine.

Interpopulation variation at Haslar, Gosport

For the Gosport population of 30 individuals (Sup-porting Information Table S2), we have data on ribs (30,from 29 individuals), femora (22, from 21 individuals),

and dentine (25). Of these, 15 individuals have measure-ments on all three, a further nine have paired rib-den-tine, four have paired rib-femur, and one has paired fe-mur-dentine. We are therefore in a position to comparethe isotopic values of different skeletal elements of thesame individual, to look for evidence of dietary variationbetween childhood, as given by dentine values in perma-nent teeth, reflecting growth up to 16 years of age forthe premolars and first and second molars, as sampledhere (Schroeder et al., 2009; Table 2), the last 10 years(very approximately) of life (femur), and the last (alsovery approximately) 5 years of life (rib). These latterestimates of bone turnover rates are extremely variablebetween individuals, and are loosely based on measure-ments of turnover rates of the cortical and cancellouscomponents of the ilium of elderly females, given asmean bone life spans of 5.6 years for cancellous and 13years for cortical (Parfitt, 2002; Table 1).Figure 2 compares the isotopic values obtained on ribs,

femora, and dentine for this population. Although the aver-age isotopic values for all three bone types are virtuallyidentical (see Table 2), there is a significant differencebetween the dispersion of the values. The femora aretightly grouped (range for d13C 219.3 to 221.1% and d15N10.2 to 13.4%), whereas the ribs are slightly more dis-persed along the d 13C axis (range for d15N 10.8 to 13.2%,but for d13C 217.8 to 221.2%). The dentine, however, hasa similar dispersion to the ribs in d13C (217.1 to 220.9%),but the d15N values are much more widely distributed (8.4–14.8%). This is consistent with a skeletal population drawnfrom a wide variety of dietary habitats in childhood, butconverging on a more consistent diet in maturity.Where we have measurements from two or three skel-

etal elements from the same individual, we can comparevariation within a single skeleton. Calculation of the dif-ference in d13C between measurements on ribs and fem-ora (D 5 rib 2 femur) shows no particular pattern in the20 pairs available in Supporting Information Table S2.The average difference is 0.01% (range for 21.1 to11.1%), with 10 negative and 9 positive differences (onezero). For the difference in d15N between ribs and fem-ora, the average is 0.29% (range for 20.8 to 1.5%), withfive negative and 12 positive (three are zero). Compari-son between the 24 pairs of rib-dentine values (one sam-ple, HAS 09 B221, has two rib measurements, giving 24pairs but from 23 individuals) reveals an average differ-ence (rib-dentine) of 20.20% for d13C (range for 21.6 to11.6%, 15 negative and 8 positive) and 10.37% for d15N(range for 22.4 to 13.4%, 8 negative and 14 positive).The rib-femur isotopic spacing is, therefore, on averageclose to zero for both isotopes, but there is some slightindication of a small reduction in the d13C value(becoming on average 0.2% more negative) and the d15Nvalues being enriched on average by 0.37% in therib-dentine spacing.

TABLE 2. Average values for Plymouth ribs and Haslar ribs, femora, and dentine

% Collagen yield %C %N C/N ratio d13C (% V-PDB) d15N (% AIR)

Plymouth ribs (n 5 50) 5.9a 32.4 11.5 3.3 218.8 11.1Haslar ribs (n 5 30) 10.8b 29.0 10.2 3.3 220.0 11.9Haslar femur (n 5 22) 5.9c 29.1 9.9 3.4 220.2 11.7Haslar dentine (n 5 25) 1.6d 32.6 11.8 3.2 219.8 11.6

a n 5 38.b n 5 17.c n 5 15.d n 5 11.



Because, as shown in Figure 2, the individual valuesfor the isotopes in the dental collagen are potentiallyhighly variable, reflecting a range of preadult dietaryregimes. It is more interesting to compare the rib-den-tine spacing of the isotopes with the isotopic value in thedentine. If, as suggested above, the trend is for more di-vergent isotopic values of dentine (childhood) to convergeon a more standardized value (reflecting the controllednaval diet in adult life), then we should expect the rib-dentine spacing to become more pronounced as a func-tion of increasing difference between dentine collagen(starting) values and the end point (rib values). Figure3a shows a plot of D13C (rib–dentine; i.e., the differencebetween the rib and dental values for d13C) against thevalue of d13C in the dentine, and Figure 3b shows thesame plot for d15N. In both figures, but most strikinglyin Figure 3b (d15N), there is a linear relationshipbetween the rib-dentine spacing and the value in thedentine, suggesting that the magnitude and direction ofthe spacing is dependent on the starting value, thus sup-porting the above suggestion.

Intrapopulation variation: ribs from Gosportand Plymouth

Although ribs, femora, and dentine have been ana-lyzed from the 30 individuals at Gosport, to carry out acomparison between these two approximately contempo-rary assemblages, we focus on the ribs in this section,since we only have rib data from the 50 individuals fromPlymouth. Figure 4 shows an isotopic plot of both sets ofdata. For both populations, the range of values for d13C

(Plymouth mean d13C 5 218.8 6 1.0%, Gosport d13C 5220.0 6 0.8%) suggest a diet generally consistent witha European C3-based diet, as expected from the detailsof the rations provided, discussed above. The nitrogenvalues are relatively high, suggesting a high-protein dietrich in either terrestrial meat or aquatic foods (Plymouthaverage d15N 5 11.1 6 1.4%, Gosport d15N 5 11.9 60.6%). The lines of regression for each population are:

Plymouth : d15N ¼ 0:583d13Cþ 22:0&ðr ¼ 0:42Þ

Gosport : d15N ¼ 0:023d13Cþ 12:2&ðr ¼ 0:02ÞThe lack of relationship between d15N and d13C for the

Gosport population can be taken to largely rule out thelikelihood of a significant marine contribution to thediet, but there is a significant correlation for Plymouth (t5 3.21; significant at 95%) between higher d15N valuesand higher (less negative) d13C values, which might beexpected to accompany a diet with a variable contribu-tion from a marine component (DeNiro and Epstein,1981).However, the most striking aspect of Figure 4 is the

apparent displacement of the Plymouth data toward lessnegative values of d13C, with only a small difference inthe d15N values [the differences in the means of bothd13C (t 5 6.7) and d15N (t 5 3.6) are significant at the95% confidence level]. This is more likely to be theresult of a C4 contribution to the diet. Carbon isotopescan be used to differentiate between plants that use theC3 pathway and those that use the C4 pathway. Isotopicfractionation occurs during the uptake and conversion ofatmospheric CO2 into plant tissue: plants following themore common C3 pathway (trees, most shrubs, and com-mon temperate domesticates such as wheat, barley, oats,and rye as well as most fruits and vegetables) discrimi-nate strongly against 13C resulting in a d13C value rangeof 222 to 234% (van der Merwe and Vogel, 1978; vander Merwe, 1982). In contrast, plants using the C4 path-way, mainly tropical grasses, discriminate against 13C toa lesser extent giving a less negative range of 28 to216% (mean 212.5%; Vogel, 1980). These plants includemaize, sugarcane, sorghum, and millet. The slight dis-placement of the Plymouth population toward less nega-tive values of d13C is indicative of a population withsome access to C4 foodstuffs, or to animals, which havebeen fed on C4 fodder. Some individuals have isotopicvalues indicative of a substantial input of C4 protein(especially Sk 844, with d13C 5 216.2% and d15N 511.7%, but nine others (Sk 571, 590, 602, 657, 668, 730,

Fig. 3. (a) Plot of the difference between rib and dentine val-ues of d13C against the value of d13C in the dentine for theGosport samples. (b) Plot of the difference between rib and den-tine values of d15N against the value of d15N in the dentine forthe Gosport samples.

Fig. 4. Comparison of isotopic values on ribs from Plymouthand Gosport.

6 P. ROBERTS ET AL.


754, 757, and 835) have d13C values less negative than218%). Given the supposed uniformity of rations aboardship during the period in question, it is intriguing toinvestigate this apparent difference further, with refer-ence to data from other populations.

Comparison with other populations: NorthAmerica

As stated above, the operational period of both thehospital cemeteries spanned the American Wars of Inde-pendence (1775–1783), the Anglo-American War (1812)as well as the Napoleonic conflicts (1799–1812), all ofwhich would have led to British vessels serving acrossdiverse regions of the world, and possibly recruiting indi-viduals with dietary baselines very different to those ofBritish servicemen. Furthermore, it was noted from thedocumentary evidence that the Plymouth hospital buri-als did include prisoners-of-war from North America.Analysis of a sample of surgeon’s logs of RN ships thatdeposited the sick and hurt at Haslar and PlymouthHospitals between the years 1750 and 1826 (ADM101/80-127) shows that a higher proportion of the ships dock-ing at Plymouth were involved in service across the At-lantic in the Caribbean and the Americas (Fig. 5). Ineach case, the areas of service of the vessel wererecorded, with each vessel only being recorded once, butdifferent areas of service for the same vessel wereincluded.To test the hypothesis that the observed difference

between the isotopic values at Plymouth and Gosport isdue to greater contact of the vessels docking at Plym-outh with the Americas, we have compared these datawith published values from three broadly contemporaryAmerican populations. The most direct comparisonchronologically is with the US soldiers buried at SnakeHill, Fort Erie, Ontario (Raynor et al., 2008). Thisassemblage comprised US soldiers including the fifthPennsylvania Volunteers, the New York Militia, and

Native American soldiers, who died around the time ofthe battle on August 15, 1814. A sample of bone collagen(from unspecified skeletal elements) from 15 soldiers wasisotopically analyzed. The second comparative dataset isfrom 16 burials from the Patuxent Point, near Solomons,Virginia, in the Chesapeake Bay area dating from 1658to the mid-to-late 1680s (Ubelaker and Owsley, 2003).Osteological evidence of strenuous physical activity andhistorical documents suggest that this burial groundrelated to a tobacco plantation on the site. The finaldataset used is that of Schroeder et al. (2009), who ana-lyzed 25 enslaved Africans from the Newton plantation,Barbados, dating to between the late 17th and the early19th centuries. This dataset is included not particularly,because we expect any of our servicemen to have a dietsimilar to these slaves, but to allow us to contrast the di-etary trends on the east coast of North America withthose of the lowest classes in the Caribbean, since Figure5 shows that British Naval ships visited both places. Wehave used the data on rib samples for comparison.Figure 6 shows a comparison of these three datasets

with the rib data from Plymouth and Gosport. It is clearthat, while none of the Plymouth individuals have ashigh a C4 dietary component as the American soldiersfrom Ontario or the tobacco plantation workers fromChesapeake Bay, the general trend of the Plymouth sai-lors is in the same direction as these populations, andquite different to the Caribbean slaves. This suggeststhat some of the Plymouth sailors either originated fromeastern North America (especially perhaps Sk 844), orhad spent some time on the Atlantic seaboard of NorthAmerica. Historical evidence suggests that the largelyC3-based naval rations could be supplemented with otherfoodstuffs from local produce when abroad, and for NorthAmerica this is likely to have involved significantamounts of C4 staples (maize and possibly sugarcane ormolasses). The latter nonproteinaceous ‘‘supplements’’(including rum) would, however, have had very littleimpact on the isotopic values in the collagen, since pure

Fig. 5. Pie charts showing the areas of service of ships listed between 1790 and 1816 from which patients to Plymouth andPortsmouth came. This was determined using the National Archives. Although the number of ships analyzed for both ports was 26,the total is larger because where multiple destinations were noted they have been taken into account.



sugar and alcohol are only detectable in the carbonated13C values (Ambrose et al., 1997). The data from theAfrican slaves (or descendants of African slaves) fromBarbados show a substantially higher average value ford15N than the two North American comparators, and donot appear to lie on the same trend line as these or thePlymouth sailors. This is probably the result of a mixedC4 and marine diet, and is quite different from thetrends noted above.It is worth remembering in this context that the May-

flower departed British shores for America from Plym-outh in 1620, so the tradition of Atlantic voyaging fromthis specific port is not a recent one.

Comparison with other populations:the Mary Rose

To add a temporal dimension to the isotopic study ofBritish Naval diets, we have used data from Bell et al.(2009) study on the sailors of the Mary Rose, which sankin the Solent off Portsmouth harbor on July 19, 1545.The Mary Rose carried a complement of 415 men, butarchaeological excavation recovered the commingledremains of a minimum of 179 individuals. Bell et al.(2009) report the isotopic analysis of 18 of these, selectedfrom different decks on the ship to give as wide a sampleof the crew as possible. From historical records, the com-plement would have included something like 185 sol-diers, 200 mariners, and 30 gunners. It is likely thatsome at least of these soldiers were mustered in Oxford-shire (Vine, 2011), which is as far from the sea as it ispossible to get in England. The isotopic bone collagen

data presented by Bell et al. (2009) was obtained fromeither mandibles or maxillae to guard against unknow-ingly sampling the same individual more than once.Figure 7 presents the isotopic data from the Mary

Rose mandibles and maxilla, compared with ribs fromPlymouth and Gosport. From the Gosport data presentedin Figure 2, we know that there can be small differencesbetween the different skeletal components in the sameindividual, so we must be cautious when comparing datafrom ribs and maxilla/mandibles. However, the MaryRose data comfortably sits in the region defined by therib analyses from Gosport and Plymouth, suggesting nogreat dietary change in Naval rations from the TudorNavy of the early 16th century, to that of Lord Nelson atthe beginning of the 19th. Table 3 shows a reconstruc-tion of the weekly rations for a man on board the MaryRose at the time of her sinking. It is essentially thesame as the diet of the late-18th century Navy (Table 1),except that stockfish (dried and/or salted cod) is explic-itly included. In their discussion of this diet, Coy andHamilton-Dyer (2005; 608) observe that the meat-richcontent, felt at the time to be necessary to support heavymanual work, would have lacked vitamins—to the pointof risking scurvy and Vitamin B complex deficiencies,which could only have been counteracted by eating freshfruit and vegetables (which were in the issued rations)or consuming beer. They also point out that the dried orsalted nature of much of the food, with limited waterintake, much in the form of small beer, would haveseverely dehydrated the seamen, especially in thesummer months. Despite these associated high healthrisks, the sea diet continued virtually unchanged untilthe mid-19th century, as salting was the only feasible so-lution to the problem of preserving food on board overlong periods.

Fig. 7. Isotopic data from the Mary Rose (Bell et al., 2009),compared with data on ribs from Plymouth and Gosport.

TABLE 3. Predicted weekly rations per man issued on the Mary Rose in 1545 (Coy and Hamilton-Dyer, 2005; Table 14.13)

Biscuit Beer Beef Pork Peas Fish Butter Cheese

Sunday 1 lb 1 gal 1 lb 1 ptMonday 1 lb 1 gal 2 lbTuesday 1 lb 1 gal 2 lbsWednesday 1 lb 1 gal ¼ 2 oz 4 ozThursday 1 lb 1 gal 1 lb 1 ptFriday 1 lb 1 gal ¼ 2 oz 4 ozSaturday 1 lb 1 gal s ¼ 2 oz 4 oz

Coy J and Hamilton-Dyer S. 2005. ‘‘Flesh, fish, biscuit, and beer’’: victuals for the ship. In: Gardiner J and Allen MJ, editors. Beforethe mast: life and death aboard the Mary Rose. The archaeology of the Mary Rose, Vol. 4. Portsmouth, UK: Mary Rose Trust.

Fig. 6. Comparison of isotopic data on ribs from Gosportand Plymouth with ribs from Barbados (Schroeder et al., 2009),and data from Chesapeake (Ubelaker and Owsley, 2003) andSnake Hill (Raynor et al., 2009).

8 P. ROBERTS ET AL.


Isotopically speaking, it is interesting to note that theaverage values for these three groups (Mary Rose, d13C5 -19.4%, d15N 5 11.4%; Gosport ribs d13C 5 220.0%,d15N 5 11.9%; Plymouth ribs d13C 5 218.8%, d15N 511.1%) are on the margins of (or just outside) theexpected range of variation for humans subsisting on apure C3 diet, which may be taken to be �222.5%\ d13C\ 219.5% and 8% \ d15N \ 10% (Schoeninger andMoore, 1992; 260). Although the recorded marine proteincontribution appears to be minimal, it seems that a regu-lar minimum marine diet of 1/4 of a salted cod threetimes a week may be on the margins of isotopic signifi-cance. Bell et al. (2009; Fig. 3) have also suggested that,because of the relationship observed between d13C andd15N in their data—increasing d15N values with decreas-ing (less negative) d13C values—there could be a contri-bution of freshwater resources (fish and/or fowl) to theMary Rose diet. In this case, this is not implausible if, assuggested above, the soldiers were mustered in Oxford-shire. Since our data (Fig. 7) encompass the same range,and in particular, the Plymouth data show a similartrend line, we have to accept that such influences mayalso be present in the 18th century diet, but the currentevidence is not compelling.Two other possibilities for slightly elevated d15N

should also be considered. First, it is likely that many ofthe people buried in the naval hospital cemetery mayhave been ill for some time before arriving at the hospi-tal. Trauma, wasting diseases and starvation may createhigher d15N values. Unfortunately, because of the lack ofdetailed medical records, it is not possible to correlatemedical histories with individual skeletons. What gen-eral records that do exist suggest that the vast majorityof patients were admitted with acute diseases, which areunlikely to have affected the long-term dietary isotopevalues measured in the bone collagen. A few of the skele-tons were identified as having pathologies consistentwith active scurvy, but this again will not have affectedthe long-term averages. Second, documentary sourcesabout diet (discussed above) do suggest the possibility oflong-term dehydration, which could indeed result inhigher values of d15N, and so we cannot discount this asa possible reason for slightly elevated nitrogen values.We would expect, however, that such effects would influ-ence both populations equally, and therefore the differen-ces we have observed are still significant.

CONCLUSION

We have taken relatively large numbers of individualsfrom two contemporary burial grounds associated withRoyal Naval hospitals in southern England, covering theperiod from the mid-18th century to the earlier part ofthe 19th century, at the height of the ‘‘Age of FightingSail.’’ These individuals for the most part, were seamenand marines, either wounded or diseased on active serv-ice. We were able to analyze ribs, femora, and dentinefor d13C and d15N in the bulk collagen of skeletons fromHaslar Hospital, in many cases, from the same individ-ual. These samples reveal a wide dispersion of values indentine, indicating that the Gosport individuals grew upin a wide range of dietary regimes, with the ribs andfemora forming more tightly grouped clusters, indicativeof a homogeneous diet in adulthood. This is demon-strated by plotting the difference in isotopic valuebetween rib and dentine against the value in the den-tine, which shows that the rib to dentine spacing

changes the most in those samples, which are furthestaway from the end-point diet. This is completely consist-ent with historical evidence for naval recruitment from awide geographical region, and with a highly prescriptivediet aboard ship. It should be noted, however, that his-torical and isotopic evidence both indicate a relativelyprotein-rich diet on board ship, compared with whatmight be expected in their terrestrial working class con-temporaries.A comparison of the average isotopic values from the

ribs of the assemblages of Plymouth and Gosport revealsa somewhat unexpected difference, given that, accordingto historical evidence, the rations on board ship wereremarkably constant wherever the ship was serving. Thesamples from Plymouth have a wider spread of d13C val-ues, with some greater than (less negative than) 218%,which shows that the diet is supplemented either by asignificant marine contribution, or the input of a C4 sta-ple such as maize. We suggest that the most likely expla-nation is the latter, either directly or through animalsfoddered on C4 protein, since the d15N values do notshow the increase that one would expect if a marine con-tribution were responsible for this increase. To supportthis hypothesis, we have compared these data with iso-topic results from US soldiers who died in 1814 at SnakeHill, Ontario, but who had been recruited from the labo-ring and agricultural classes of the Northeastern UnitedStates, and also with a group of tobacco plantation work-ers from the Chesapeake Bay area (1658–1680’s). Thesamples from Plymouth that we suggest show a C4 die-tary contribution are entirely consistent with the trendlines defined by these two populations. It seems likely(and is supported by historical evidence of ships’ areas ofoperation) that the seamen buried at Plymouth had ahigher probability of sailing to North America than thoseat Gosport, and that this contact is reflected in their die-tary isotopes. It is also entirely possible (and again sup-ported by historical evidence) that some of them mayhave originated in America, and died while prisoners-of-war in England, or as seamen who had volunteered orwere impressed into the RN. This clearly invites furtherstudy, including strontium and oxygen isotope analysisof tooth enamel, to indicate childhood origins, and hencemobility during an individual’s lifetime. Such studies arecurrently under way. The additional comparison withthe limited isotopic data available from the men of theMary Rose, which sank in 1545, allows this study to beextended chronologically. There is considerable isotopicoverlap between the Mary Rose population and those ofPlymouth and Gosport. A comparison of d15N valuesacross the three populations supports the historical in-formation, which attests to the relatively high quality ofnaval diet, with a considerable protein intake from meat,such as beef and pork, rather than fish, which was sup-plied in negligible quantities.Part of the aim of this project was to demonstrate how

biological anthropology as applied in archaeology mightnot only supplement, but also fundamentally enrich ourinformation from this particular historical period. Thisstudy is of course just the tip of the iceberg in terms ofthe investigation of 18th century diets, both in the navyand beyond. Although the isotopic data accords well tothe historical context, and the naval diet appears to berelatively consistent over time, there are significant iso-topic differences between, and potentially within, differ-ent naval populations, which are interesting to both thearchaeologist and historian.



ACKNOWLEDGMENTS

The authors thank John Pamment-Salvatore of ExeterArchaeology and Martin Brown of the Ministry ofDefence for allowing access to these skeletal assemb-lages. They are extremely grateful to Prof. Mark Harri-son, Wellcome Unit for the History of Medicine, Univer-sity of Oxford, for discussions on the historical sources.One author (CB) is grateful to the Arts and HumanitiesResearch Council and Oxford Archaeology for providinga Collaborative Doctoral Award to support her DPhilresearch. They are grateful to Prof. Julia Lee-Thorp,University of Oxford, for commenting on an earlier draftof this article, and to two anonymous referees and theeditor for providing helpful comments.

LITERATURE CITED

ADM records, 1759–1764 Death of Seamen Registers and 1794–1824 Haslar Hospital Musters. Admiralty Papers, NationalArchives, Kew, London.

Ambrose SH, Butler BM, Hanson DB, Hunter-Anderson RL,Krueger HW. 1997. Stable isotopic analysis of human diet inthe Marianas Archipelago, Western Pacific. Am J PhysAnthropol 104:343–361.

Bell LS, Lee-Thorp JA, Elkerton A. 2009. The sinking of theMary Rose warship: a medieval mystery solved? J Arch Sci36:166–173.

Blane G. 1799. Observations on the diseases of seamen. London:Murray and Highley.

Boston C. Forthcoming. Lobsters and Tars: a comparison of thehistorical and osteological evidence for the origins, lifestylesand health of late 18th – early 19th century Royal Naval sea-men and marines, with special reference to trauma and medi-cal treatment at three Royal Naval Hospitals. UnpublishedDPhil thesis, University of Oxford.

Clowes WL. 1900. The Royal Navy: a history from earliest timesto 1900 , Vol.5. London: Chatham Publishing (reprinted 1974).

Coy J, Hamilton-Dyer S. 2005. ‘Flesh, fish, biscuit and beer’:victuals for the ship. In: Gardiner J, Allen MJ, editors. Beforethe mast: life and death aboard the Mary Rose . The archaeol-ogy of the Mary Rose Vol.4. Portsmouth: Mary Rose Trust.

DeNiro MJ, Epstein S. 1981. Influence of diet on the distribution ofnitrogen isotopes in animals. GeochimCosmochimActa 45:341–351.

Hedges REM, Clement JG, Thomas CDL, O’Connell TC. 2007.Collagen turnover in the adult femoral mid-shaft: modelledfrom anthropogenic radiocarbon tracer measurements. Am JPhys Anthropol 133:808–816.

Hedges REM, Reynard LM. 2007. Nitrogen isotopes and the trophiclevels of humans in archaeology. J Arch Sci 34:1240–1251.

Hodgins I, Pamment-Salvatore J. 2009. Excavation of a mid-18th to early 19th century cemetery for Royal Naval and RoyalMarine personnel in Plymouth. Post-Med Arch 42:424–433.

Lambert AD. 2002. War at sea in the age of sail. London: Cassell.Lambert AD. 2004. Nelson: Britannia’s god of war. London:

Faber and Faber.Lavery B, editor. 1998. Shipboard life and organisation 1731–

1815. Aldershot: Ashgate.Lloyd C, editor. 1965. The health of seamen: selections from the

works of Dr. James Lind, Sir Gilbert Blane and Dr. ThomasTrotter. London: Navy Records Society.

Macdonald J. 2006. Feeding Nelson’s Navy. The true story offood at sea in the Georgian era. London: Chatham Publishing.

Macdonald J. 2010. The British Navy’s Victualling Board, 1793–1815: management competence and incompetence. Wood-bridge, UK: Boydell Press.

Oxford Archaeology. 2005a. The Paddock, Royal Naval Hospital,Haslar Gosport. Unpublished archaeological desk-basedassessment. Oxford: Oxford Archaeology.

Oxford Archaeology. 2005b. The Paddock, Royal Naval Hospital,Haslar Gosport. Unpublished archaeological evaluationreport. Oxford: Oxford Archaeology.

Parfitt AM. 2002. Misconceptions (2): turnover is always higherin cancellous than cortical bone. Bone 30:807–809.

Pugh PD. 1972. History of the Royal Hospital Plymouth. J RNaval Med Service 58:78–94.

Raynor LA, Kennett DJ, Pfeiffer S. 2008. Dietary variabilityamong a sample of United States soldiers during the war of1812. Hist Arch 42:76–87.

Richards MP, Hedges REM. 1999. Stable isotope evidence forsimilarities in the types of marine foods used by late Meso-lithic humans at sites along the Atlantic coast of Europe. JArch Sci 26:717–722.

Rodger NAM. 1986. The wooden world; an anatomy of the Geor-gian Navy. London: Collins.

Rodger NAM. 2004. The command of the oceans—a naval his-tory of Britain 1649–1815. London: Allen Lane/National Mari-time Museum.

Schroeder H, O’Connell TC, Evans JA, Shuler KA, HedgesREM. 2009. Trans-Atlantic slavery: isotopic evidence forforced migration to Barbados. Am J Phys Anthropol 139:547–557.

Schoeninger MJ, Moore K. 1992. Bone stable isotope studies inarchaeology. J World Prehist 6:247–296.

Sealy J, Armstrong R, Schrire C. 1995. Beyond lifetime aver-ages: tracing life histories through isotopic analysis of differ-ent calcified tissues from archaeological human skeletons. An-tiquity 69:290–300.

Shortland AJ, Masters P, Harrison K, Williams A, Boston, C.2008. Burials of eighteenth-century naval personnel: prelimi-nary results from excavations at the Royal Hospital Haslar,Gosport (Hants). Antiquity 82http://www.antiquity.ac.uk/proj-gall/shortland1/index.html.

Slope N. 2006. Serving in Nelson’s Navy: a social history ofthree Amazon class frigates utilising database technology(1795–1811). Unpublished PhD Thesis, Thames Valley Univer-sity, Maidenhead.

Tait W. 1906. A history of Haslar Hospital. Portsmouth, UK:Griffin.

Ubelaker DH, Owsley DW. 2003. Isotopic evidence for diet inthe seventeenth-century colonial Chesapeake. Am Antiq 68:129–139.

van der Merwe NJ. 1982. Carbon isotopes, photosynthesis andarchaeology. Am Sci 70:596–606.

van der Merwe NJ, Vogel JC. 1978. 13C content of human colla-gen as a measure of prehistoric diet in woodland North Amer-ica. Nature 276:815–816.

Vine S. 2011. The crew.http://maryrose.org/ship/crew2.htm(accessed 24/8/2011).

Vogel JC. 1980. Fractionation of the carbon isotopes during pho-tosynthesis. Berlin: Springer-Verlag.

Watt J, Freeman EJ, Bynum WF, editors. 1981. Starving sai-lors: the influence of nutrition upon naval and maritime his-tory. Greenwich: National Maritime Museum.

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