Thursday, June 10, 2010

From Whence the Scurvy Dog

After being enthralled by Steven Johnson's 2006 book on cholera, The Ghost Map, I picked another medical mystery from the library's audiobook collection, this time Stephen J. Bown's 2004 book Scurvy.

Scurvy is a medical condition caused by a scarcity of ascorbic acid. Our bodies use ascorbic acid to produce collagen, which in turn is used as a structural and connective substance throughout the body. It seems we are one of a few animals who cannot manufacture our own ascorbic acid, and so we must consume it in sufficient quantities (our bodies use up about 50 mg a day). If we fail to ingest enough ascorbic acid, our bodies' normal stores of the substance (roughly 1,500-2,000 mg) will deplete and the symptoms of scurvy will begin to emerge: swollen gums, blotchy, rubbery skin, sunken eyes, loose teeth, foul breath, and, eventually, death. Without collagen, the body literally begins to fall apart, and scurvy is what that process looks like.

Because of the necessity of spending months without fresh food, seamen in the age of sail were particular victims of scurvy. And general nutritional circumstances caused many sailors to come aboard ship already deficient in ascorbic acid, so that the normal 60-day onset of the disease upon being deprived of fresh foods was often considerably shortened. Being a sailor was an extremely hazardous occupation, the survival numbers making it seem almost like a death sentence. And it was very often scurvy that made it so; more people died of scurvy on ships than from all other causes combined, and captains attempted to staff their ships at the outset of a voyage in expectation of losing fully 50% of the men at a minimum. (In answer to the question "Why would anyone sign up for a miserable job which promised an even chance of death?" Bown shows us that very many common sailors did not enlist voluntarily. All nefarious means were used to get men on the ships--say, clubbing them and dragging them onboard while unconscious--after which any attempt to leave was considered desertion, a capital offense. Husbands regularly vanished without a trace, leaving wives and children to cope alone. This sounds like a book in itself.)

As I was with Johnson's book, I find I'm most struck by the glimpse into life without science. This, in fact, is the real story of the book. The book is peopled throughout by all manner of characters confidently prognosticating on things of which we now know--and I daresay they knew at the time--they had no knowledge or insight whatsoever.

The French mariner, Francois Pierard, writing after a 1603 voyage to the East Indies, believed that the distemper was "very contagious even by approaching or breathing another's breath." While Thomas Cavendish on a 1586 British circumnavigation of the globe suggested that scurvy was "in infection of the blood and liver." Antony Knivet recorded on a 1591 voyage through the Straits of Magellan to explore the South Seas with John Davis that "most of our men fell sick of the scurvy by reason of the extreme heat of the sun and the vapors of the night."

Bad air, exposure to sea water, heredity, contagion, rats, divine disfavor, dampness, overly-salted food, a too-hot climate, a too-cold climate, laziness, the weakness of Northern peoples; all were offered as causes of scurvy in the accounts of the early mariners.
This all reminds me so much of The Ghost Map, wherein many people insisted that cholera was caused by some kind of moral failing--even as the "godly" were felled right alongside the riff-raff.

Scurvy was a horrible condition, and without a real understanding of its causes it must appear mysterious in the extreme. The period is marked by increased crowding in cities and on ships and by an almost total ignorance of sanitation. One figure in the book claimed (I must paraphrase) that during the great naval battles between England and France in the 17th and 18th Centuries, something like 185,000 men were enlisted for work on the ships, and over 133,000 of them were never to see their home soil again. And yet only about 1,000 men died as the result of battle action. The rest were felled by disease, and a huge number of those by scurvy. The book makes a specific case of the voyage of Lord Anson in 1740-41, who departed England with a flotilla and some 2,000 men and lost some 85% of them in the next three years, almost all to scurvy. The horrific daily loss of men caused the captain to have to abandon and scuttle his ships--ultimately all but one--because there were no men even to sail them (to say nothing of the 6-10 men needed to man each of a ship's 50 or 60 guns).

And so the business of knowing what causes scurvy and how to treat it was a subject of national--even worldwide--importance, and in the absence of the scientific method (and many other scientific advancements which lay yet in the future) there was only a scattershot trial-and-error. This was compounded by all manner of speculation and political jockeying coupled with a peculiar failure to make careful observation (again, the importance of impartiality was yet to be realized). And the whole business was often intermingled and corrupted by the profit motive. As with cholera, there seem to have been scores of people attempting to profit from the condition by offering all manner of remedies, virtually none of it, we now see, with even a shred of scientific merit. The status of a person making an argument was given a good deal more weight than the stand-alone merits of their argument, which is incomprehensible to us today (argument from authority--or its converse, the ad hominem attack--being commonly recognized as a flaw in reasoning).

Theorizing (controlled theorizing) is a part of science, and my thoughts run less to the condemnation of those who speculated in the absence of good information; without the basic scientific toolkit how could one do otherwise than to speculate? Rather I'm amazed to see how total has been science's triumph over this and so many, many similar fields.

And yet the resistance and skepticism toward science and to rationality remains, at times fiercely so (as a recent comment stream on this site demonstrates).

Perhaps it's only an accurate reflection of the trials of conquering scurvy, but Bown's book strikes me as too long by half, even though it's not a particularly long book. A good deal of print space is devoted to the crackpot theories concerning scurvy, and this territory is revisited again and again throughout the book. Part of this, as I allude, might just accurately reflect how difficult was the discovery of a cure for the condition when, say, no one knew what ascorbic acid was or how to isolate it or what nutritional value it had. And even though the most striking thing I take from the book is this glimpse back on a world without science, it still seems like the point is amply made early on.

As a medical condition, scurvy may well have towered over cholera in pre-scientific times. But as literature, Bown's book on scurvy takes a distant second to Johnson's book on cholera. The Ghost Map is a much more gripping read.


CyberKitten said...

I love books like that.

wunelle said...

If you haven't read Johnson's The Ghost Map, I highly recommend it!