Monday, 22 April 2019

Victualling Victoria's Navy - 1. Chocolate

As mentioned in my previous post, I am currently attempting to assemble the necessary provisions to perform a reasonably authentic simulation of the diet of the early Victorian Royal Navy. The intended duration is  one week, but if it goes smoothly then maybe I'll try it for a longer period at a later date.

In his book, The Voyage of the "Fox" in the Arctic Seas, Francis McClintock reported the discovery of nearly forty pounds of chocolate in the deserted boat at Erebus bay. This was the only substance of any nutritional value among the remains recovered from the expedition.

Cocoa, the liquid, made in this case, from chocolate, the solid, was the standard breakfast of the Royal Navy from the first quarter of the 19th century onward. The ration was one ounce per day to make one pint of the drink. Originally the roasted beans (sometimes confusingly referred to as cocoa nuts) were supplied to the ships, and preparation of the cocoa involved pounding with a large mortar and pestle, but by the late 1830s the prepared chocolate was manufactured in government owned mills at Deptford, London. After some problems, celebrated chemist Dr Andrew Ure was consulted in 1842 to troubleshoot the manufacturing process. 

For my experiment in making Navy chocolate, I started with a bag of cocoa nib, which simply consists of cocoa beans which have been roasted and then cracked into small pieces. I soon discovered that my kitchen was lacking a grinder which could mill these fine enough so I next purchased a bag of cocoa mass. This is still the pure bean after it has been ground to a minute degree of fineness, and in this case moulded into buttons.

Sources slightly later than the Franklin era refer to two sorts of cocoa: "Ordinary", for which the only added ingredient is sugar, and "soluble" or "optional", which also includes a quantity of starch such as arrowroot or sago flour. It appears that only the "ordinary" sort would have been supplied to Franklin's ships but that formulation has the disadvantage that it must be boiled with water for several hours before the mixture thickens satisfactorily. The "soluble" version was quicker to make, so it could be handed out to men on duty during cold nights.

As I wanted to make both types, I melted the cocoa mass in a small pan and compounded my version of the "ordinary" with 16% sugar and the soluble with 18% sugar and 18% arrowroot starch. The proportions are from an 1895 source. Extra sugar is added when the chocolate is boiled up to make the drink.

The slabs of chocolate looked good, but upon boiling up an ounce of each to make the liquid cocoa drink, both samples seemed to me to be somewhat too thin. Because of that, the example of the finished product pictured below has been thickened by the addition of a little finely milled oatmeal. It may look a bit like cold gravy in this photo, but I can attest that it is delicious.

Cocoa remained a staple in the Navy, even into the Cold War era. Referred to as "Pusser's Kye" (or Ki) it is still reminisced over, particularly for its properties in fending off the cold. Many a sailor must have sung its praises during the cold watches of the night. Many thanks to YouTuber Scoutforlife for permission for sharing this piece of oral history which was passed down from his father. Explanation of some of the terms can be found in his post "How to make Kye". Various versions can be found, dating from WWII or earlier, with varying amounts of profanity.
Up in the Arctic Circle, where the pongos have never been,
Lie the bodies of many a matelot, and many a Royal Marine.
Cold, cold as charity.
Cold, by Christ, that's chilly,
But not as cold as Willy.
He's dead poor bugger he's dead.
It was the cold that got him,
His oppo had forgot him,
And didn't bring him any midnight kye.
The morning watchman found him,
His frozen coat around him,
And took him to the sickbay, there to die.
Cold, cold as the hairs on a polar bear's chuff.
Cold as custard on pusser's duff.
Cold, by Christ, that's chilly,
But not as cold as Willy.
He's dead poor bugger he's dead.
For several reasons, I find this strangely appropriate when thinking of those Arctic voyagers of a different era.

Saturday, 13 April 2019

My talk at Mystic Seaport

It was a real honour for me, and a great pleasure, to participate in the symposium
 which was hosted by the wonderful Mystic Seaport Museum on Friday, April 5, 2019.

My part in the show was as the second speaker on a panel with John Geiger and Keith Millar. Our set was billed as:
 “Of Ships and Men: What can modern forensics tell us about their fate?”

A "Goldner's Patent" tin can

I started off with an image of a replica Goldner's soup can and explained that the story of these cans and the mystery of the lead detected in the human remains had fascinated me more more than a decade.

Lead has some surprising properties, it is resistant to strong acids like Sulphuric acid, but is attacked by weak acids such as may be found in fruit juice. There have been documented cases of people getting lead poisoning from fruit juice served in lead-glazed ceramic jugs brought home as souvenirs.

Distillation has also been a culprit. As water condenses from vapour it absorbs carbon dioxide from the air to make carbonic acid. This weak acid has been implicated in poisoning cases where lead-soldered radiators were employed as condensers in illicit moonshine stills, and in crudely constructed rum distilleries in the eighteenth century West Indies.

Canned tomatoes have been also been a cause of lead poisoning, the fruit's acid leaching lead from the soldered seams of the cans. This principle has famously been proposed as the source of the lead exposure on the Franklin expedition, but faces the obstacle that the only canned provisions which appear in the expedition's victualling manifests are of low-acidity. There are canned meats and soups, but no canned fruit or other acidic canned products are listed.

I feel considerable sympathy for Stephan Goldner, the supplier of the canned food, or "preserved provisions" as it was called in the day. Goldner is reported to have had a prickly personality but his downfall was caused by a change to the production process, requested by the Admiralty, some time after the Franklin expedition had sailed. Nonetheless, from the early 1850s, when the scandal of the putrid meat in the Naval storehouses erupted, Goldner was villified for decades. He was called a miscreant and a traitor, one old Arctic hand even wrote that he should have been hanged - twice.

That abuse is not connected in any way to the lead from cans theory, which is a valid scientific hypothesis, albeit one which I have argued against.

Frazer stove from Peter Carney's paper
Original artwork by Kristina Gehrmann
I next mentioned the work of my great friend, the late William Battersby. William had, in 2008, published a paper in the online Journal of the Hakluyt Society with the confident title "Identification of the probable source of the lead poisoning observed in members of the Franklin expedition". 

On first reading, I found his paper compelling. William had gone back to the dockyard drawings of the ships, and nineteenth century patent documents, and from these he had synthesised a brilliant interpretation of the technical systems of the ships, including the conclusion that freshly distilled water produced by a modification to the Frazer's Patent cooking stove was at the root of the lead poisoning story. This distilled water, being mildly acid, would dissolve lead from any piping or soldered joint in the apparatus.

However, several of William's interpretations of the evidence proved questionable and were later reinterpreted in our co-authored paper, for the Newcomen Society, on the equipment of the ships. Perhaps most significant is the fact that a simple comparison of physical constants (latent heat of fusion = 334 joules per gram, latent heat of vaporisation = 2,230 joules per gram) suggests that for a given quantity of heat energy you get more than six times more water by melting ice than you get by boiling water for distillation. In other words, making drinking water by distillation of sea water is an insane waste of energy if there is ice or snow available to melt.

My subsequent paper built on William's work but used evidence from Ross and Crozier's Antarctic voyage that indicated drinking water was routinely made by melting ice in the stove's coppers or boilers. The snow tank above the stove would in this case serve only to condense excess steam arising during use of the stove for cooking. My idea was that some of this steam might condense in the (probably) lead pipe leading to the snow tank, dissolving lead and carrying it down into the coppers. There it would contaminate the day's production of drinking water made by melting ice in the coppers immediately they were free after cooking dinner was completed.

I know that I surprised a few people when I said that, for various reasons, I no longer believed my own cherished theory and that I now regard some of my interpretations of the evidence as incorrect. My current view is that the vast majority of the lead found in the bones of Franklin's men was laid down in their bones during their lives before they joined the expedition, even before they went to sea.

My next move was a theatrical flourish. I reached into my pocket and pulled out this:

a brightly coloured lollipop
There have been various suggestions for potential sources of lead exposure in the Victorian period. Lead piped water supplies are often mentioned but I think that, at this early period, such luxuries as indoor plumbing were only for the rich. Adulterated food seems more likely to me, and of the various foodstuffs mentioned in the contemporary literature the one which stands out can be summed up as "Poisonous Coloured Confectionery". I listed some of the (possible) pigments used in candy of the period:
City of London Medical Officer Dr. Henry Letheby, stated in evidence to a Parliamentary Committee:

... of all adulterations of that kind, introduction of poisonous pigments into confectionery is the most common and the most serious, There is not an article of confectionery in this country which is not so coloured, I have before me a sample of such confectionery, in which there is enough chromate of lead to do serious mischief,...
Coloured candy of the era was truly the "mutual friend" of doctors and gravediggers.

I promised every member of the audience a lick but no one took me up on the offer ☹️

A traditional style sweetshop
My local sweetshop

What about the spongy bone! I hear you cry. Anne Keenleyside's marvelous analysis of the bones found on King William Island shows a high ratio of lead levels between the spongy (trabecular or cancellous) bone and the dense (cortical) bone. Spongy bone has a large surface in contact with the blood, so its lead content is indicative of blood lead levels. Lead incorporated in the mineral structure of dense bone is locked away out of reach of the blood. Comparison with the same ratio for workers exposed to atmospheric lead pollution, led to the conclusion that the lead exposure was relatively recent.

However, there are circumstances in which lead locked away in the dense bone is released into the blood stream. One well known example is pregnancy, which must be considered unlikely in this case. A better example can be found in cases of treatment of obesity by gastric banding. In such cases the body seems to exhibit a starvation reflex and starts mining the bones. In the case of Franklin's men the comparison is obvious, lead which had been laid down in the dense bone many years before was released into their blood stream while they were starving to death.

There are other cases where comparisons with healthy modern people subject to atmospheric pollution are not helpful. After all, there was no lead smelter or automobile battery factory in the vicinity of the ships.

But what about the lead in the hair! Surely that proves they were ingesting lead during the expedition?

Well, no. Firstly the lead levels in the hair are extraordinarily high. In the case of John Torrington about twenty times the level of a man who was deliberately poisoned to death, with lead, by a love rival. Clearly, Torrington did not ingest twenty times the lethal dose of lead week after week in the months before his death with no signs of lead poisoning. The vast majority of the lead in the hair must therefore be from an external source and not from his diet.

This another case where comparison with atmospheric pollution is not helpful. When hair is contaminated with lead particles from the air, a high proportion can be washed off using detergents or organic solvents. Stronger reagents such as EDTA or mineral acids may remove even more but run the risk of confusing the analysis by leaching out lead incorporated within the body of the hair.

The situation is different when hair absorbs lead in a mildly acidic aqueous solution. In this case it seems the lead ions are exchanged for ions from within the hair. The lead in this case is like a permanent dye and is not removed by the standard laboratory washing procedures.

In his memoir of the 1875 Arctic expedition, George Strong Nares wrote:
The greatest annoyance of all, and which has never yet been completely avoided in Arctic ships, was the moisture which collected on the beams of the messdeck, to such an extent as to necessitate their being frequently sponged in order to prevent it dripping.

Nares' ships didn't have the advantage of the Sylvester stove for heating the ship but there can be little doubt that condensation was an issue on Erebus and Terror.

The water condensing on the beams will have absorbed carbon dioxide from the air, creating carbonic acid. This mild acid will have leached lead from the painted surfaces of the beams. It may have dripped onto the men directly or been transferred to their hair as they wiped their fingers through it. The hair will have absorbed lead ions from the mildly acidic aqueous solution. The lead, tightly bound to the hair, would go on to confound scientists who were more familiar with the loosely bound hair-lead resulting from atmospheric pollution.

So, in short, my answer to the Franklin expedition lead question is paint. Lead paint on the candy. Lead paint on the ships.

My researches on the subject sparked a wider curiosity into the diet of the seamen of the era, which led me to start work on a simulation project. My plan is to live for one week solely on the seaman's diet of ships biscuit with either salted or canned meat on alternate days, plus the various other foodstuffs in the manifests. When I mentioned this to John Geiger he immediately replied "No! Do it for a year!". Well, we'll see.

As you can see in this photo, I already have most of the necessary stores assembled.

Salt meat, ship's biscuit, and various other Naval foodstuffs

The Goldner cans are the only major hurdle left for me to overcome. They have been supplied as kits by Master Tinsmith Shay Lelegren of Hot Dip Tin. I will assemble them using 60/60 Tin/Lead solder and they will be filled and heat processed in as close a simulation to the original process as possible. It goes without saying that I will have medical monitoring during the period and intend to provide samples which may contribute to the scientific understanding of the seaman's diet of the era. By this I mean things like blood and hair samples and not, as someone suggested, my autopsy.

Many thanks to my fellow panellists, and in particular to Nicholas Bell for his hospitality at Mystic Seaport and to Russell Potter for his fantastic work in making this fabulous event happen.

Victualling Victoria's Navy - 1. Chocolate

As mentioned in my previous post, I am currently attempting to assemble the necessary provisions to perform a reasonably authentic simulati...