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FG-014 Historical hoax · San Francisco Bay 1977

The Drake Plate of Brass — a club’s private joke that a famous historian mistook for treasure

forged-artifactforensic-analysis1970-1999
The fake
A brass plate forged as Drake's 1579 California claim
Fooled
Herbert E. Bolton; UC Berkeley bought it for $3,500
Exposed
1977 Berkeley Lab neutron activation analysis
Status
Debunked

Summary

In 1936 a young store clerk named Beryle Shinn picked up a corroded brass rectangle near San Francisco Bay, and the following spring the most distinguished historian of the Spanish borderlands in America, Herbert Eugene Bolton of the University of California, Berkeley, announced it to the world as one of history's lost treasures. The plate appeared to be the brass tablet that Sir Francis Drake had nailed to a post in 1579 to claim "Nova Albion" — the California coast — for Queen Elizabeth I. Bolton declared on 6 April 1937 that "the authenticity of the tablet seems to me beyond all reasonable doubt," and the California Historical Society bought it for $3,500. It became a centerpiece of the Bancroft Library and a fixture of California's founding story for forty years.

It was a fraud, and an accidental one. The plate had been manufactured around 1933 by members of E Clampus Vitus, a jovial California fraternity of history enthusiasts, as a private practical joke aimed at Bolton, himself a member, who was known to dream of finding Drake's plate. The hoaxers even painted the initials "ECV" on the back in fluorescent paint, invisible in ordinary light, intending Bolton to discover the gag once he turned the plate over under ultraviolet. He never did. By the time the plate surfaced in his office, the joke had escaped its makers' control, and none of them could find a way to confess without humiliating a colleague and a major institution.

The forgery was finally and definitively exposed in 1977, when Helen Michel and Frank Asaro of the Lawrence Berkeley Laboratory subjected the metal to neutron activation analysis. The brass contained far more zinc than any sixteenth-century alloy — zinc was not isolated and added to brass deliberately until centuries after Drake — and far too little of the trace nickel, lead, gold, and iron that period brass carried. X-ray and gamma-ray tests showed the plate had been rolled smooth by modern machinery, not hammered by hand. The metal was modern American brass, most likely made between the late nineteenth and early twentieth centuries. In 2002–03, historians Edward Von der Porten, Raymond Aker, Robert W. Allen, and James M. Spitze published the full reconstruction of who made the plate and why.

The case is a study in how a respected expert's longing for a particular discovery can override every warning sign. Doubts about the plate's spelling, lettering, and manufacture were raised almost immediately, yet the authority of Bolton's name carried it past them for a generation. The joke's intended punchline — the hidden "ECV" — sat on the object the whole time, unread.

Timeline

17 Jun 1579
The real claim
Sir Francis Drake reportedly posts a brass plate during his Pacific voyage to claim "Nova Albion" for Elizabeth I; the original is never found.
c. 1933
The plate is made
Members of E Clampus Vitus fabricate a brass plate as a private joke for fellow "Clamper" Herbert Bolton, painting "ECV" on the back in ultraviolet paint as the intended reveal.
1933
First find, discarded
Chauffeur William Caldeira finds the plate near Drakes Bay, keeps it briefly, then tosses it from a car along the road near San Rafael.
Summer 1936
Rediscovery
Store clerk Beryle Shinn picks up the same plate while stopped near San Quentin, on San Francisco Bay.
Feb 1937
Brought to Bolton
Shinn shows the plate to historian Herbert E. Bolton at UC Berkeley, who has long hoped to find Drake's plate.
6 Apr 1937
Public authentication
Bolton announces the plate to the California Historical Society as a genuine "long-lost historical treasure."
1937
Purchase
The California Historical Society buys the plate for $3,500 and deposits it at the Bancroft Library.
1938
Lab endorsement
Columbia University metallurgists Colin Fink and E. P. Polushkin report the plate consistent with old brass, calling it "the genuine Drake Plate."
Early 1970s
Re-examination begins
Approaching Drake's 400th anniversary, the Bancroft Library commissions new scientific tests.
1977
The verdict
Berkeley Lab's Helen Michel and Frank Asaro find anomalous zinc and modern manufacture by neutron activation analysis, dating the brass to the modern era.
2002–03
The makers named
Historians publish the full account in California History, identifying the E Clampus Vitus hoaxers and the hidden "ECV" mark.

A historian who wanted to find Drake's plate

Herbert Eugene Bolton was no credulous amateur. He was the foremost academic historian of Spanish and early exploration in the American West, the director of the Bancroft Library, and a charismatic teacher whose lectures filled halls. He had also spoken often of his hope that Drake's lost plate of brass might someday be recovered on the California coast, and he had encouraged students to keep watch for it. That public wish was widely known — including to his fellow members of E Clampus Vitus, a fraternal order that mixed antiquarian enthusiasm for California history with conviviality and elaborate pranks.

This is the crucial precondition of the deception: the target had already announced, in advance, exactly what he wanted to find. When a corroded brass plate bearing a 1579 date and Drake's name reached his office, Bolton did not approach it as a neutral puzzle to be solved but as the fulfillment of a long-held hope. His announcement that the plate's authenticity was "beyond all reasonable doubt" was made within weeks. The institution he led then converted his personal conviction into a $3,500 purchase and a permanent place of honor, lending the plate the prestige of the Bancroft Library and the University of California.

A joke engineered to be discovered — and missed

The plate was never meant to fool anyone for long. Its makers — among them George Clark, who hammered the letters with a cold chisel; George Haviland Barron, who designed it; and others who sourced the brass from a San Francisco shipyard — built in a safety valve. Lorenz Noll and Albert Dressler painted "ECV," the fraternity's initials, on the reverse in paint that fluoresces only under ultraviolet light. The intent was that Bolton, on examining his prize closely, would turn it over, see the mark, and recognize the gag from his own club. George Clark even stamped a small "C.G." near Drake's name — his own initials reversed — which authenticators later misread as standing for "Captain General."

The plan failed at the first step: the plate did not reach Bolton promptly. After its first finder discarded it, it lay by the road for years before Shinn found it again and carried it to Berkeley, by which point the original prank context had evaporated. Bolton, certain he held the real thing, never thought to inspect the back under ultraviolet for a fraternity's mark, because nothing in his framing of the object suggested he should. The hoaxers, watching their colleague stake his reputation on their forgery before a learned society, found themselves trapped: a confession would have publicly humiliated a respected friend and a great library. They tried oblique hints — a privately printed parody booklet teasing the spelling errors and the impossibility of the metal — but never a plain admission, and the plate stood as genuine.

The metal that could not lie

What connoisseurship and goodwill could not settle, physics did. The authentication of the 1930s rested on metallurgists comparing the plate's surface and corrosion to expectations for old brass — proxies that a modern fake could satisfy. The 1977 re-examination instead measured the metal's actual elemental composition. Neutron activation analysis at the Lawrence Berkeley Laboratory, performed by Helen Michel and Frank Asaro and cross-checked against work at Oxford's archaeometry laboratory, found that the plate's brass was wrong in two directions at once. It carried markedly more zinc than sixteenth-century brass could contain, because deliberate, controlled zinc-alloying of brass postdates Drake's era; and it carried far too little of the nickel, cobalt, silver, gold, lead, and iron that genuine period brass picked up from impure ores.

The physical form betrayed it too. X-ray diffraction and gamma-ray absorption showed the plate was uniformly thin and smooth, consistent with modern rolling mills rather than the uneven hand-hammering of a Tudor workshop. Taken together, the evidence pointed unambiguously to American brass manufactured between roughly the late nineteenth century and the early twentieth — entirely consistent with a plate fabricated around 1933. The Bancroft Library accepted the finding, and the plate was reclassified from national treasure to elaborate forgery. The 2002–03 scholarship by Von der Porten, Aker, Allen, and Spitze then supplied the human story behind the metal, naming the Clampers and confirming that the long-overlooked "ECV" in fluorescent paint had been the intended confession all along.

The Five Factors

01
The pre-announced wish
Bolton had told the world he hoped to find Drake's plate, so when an object answering that description appeared, he received it as a fulfillment rather than a question. A discovery that exactly matches a known longing should be scrutinized more, not less; the forger's easiest target is the expert who has already described his ideal find.
02
Authority converted into institutional fact
One eminent historian's rapid endorsement was enough for a learned society to purchase the plate and a great library to enshrine it, and that institutional setting then vouched for the object to everyone downstream. When a single famous name substitutes for repeated independent testing, error inherits the full prestige of the institution that adopted it.
03
Authentication that tested proxies, not the metal
The 1930s examination compared surface and corrosion to expectations for old brass — features a modern plate could mimic — rather than measuring the alloy's actual composition. A test that checks appearances can be defeated by appearances; only when analysis addressed the elemental fingerprint of the metal did the anachronism become undeniable.
04
The unread safety valve
The hoaxers built in a confession — fluorescent "ECV" lettering on the back — but its discovery depended on someone choosing to look skeptically, and the plate's accepted status guaranteed no one would. Built-in disclaimers and hidden marks fail whenever the audience has already decided the object is real; a warning only works if it is read.
05
The trap of sunk reputation
Once Bolton had publicly staked his name and his library's money on the plate, the people who knew it was fake could no longer easily speak, because exposure would humiliate a respected colleague and institution. Social cost can keep a known falsehood standing for decades; the longer a fake is honored, the more painful — and therefore the less likely — its correction becomes.

Aftermath

The plate's exposure was a quiet embarrassment rather than a scandal, partly because Bolton had died in 1953, still believing in his discovery, and partly because the perpetrators had clearly intended mischief, not profit. No one was prosecuted; E Clampus Vitus is a fraternity, not a fraud ring, and the joke had simply outrun its authors. The Bancroft Library retained the plate, but as a documented forgery — a teaching object about the limits of expert certainty rather than a relic of Drake.

The case became a standard cautionary tale in American historiography and in the developing field of archaeometry. Neutron activation analysis, still novel in the 1970s, demonstrated its power to settle authenticity questions that connoisseurship had left open for forty years, and the anachronistic-zinc finding sits alongside the synthetic pigments that undid later forgeries as a classic instance of chemistry catching what the eye missed. What remains contested is only the fine detail of which Clampers did exactly what; the central facts — that the plate is modern, that it was a prank, and that the confession was hidden on its own back — are settled.

Lessons

  1. Be most suspicious of the find that perfectly satisfies a desire you have already made public; a forger's surest bait is the discovery you have announced you are hoping for.
  2. Do not let one authority's endorsement become an institution's verdict; require independent re-testing of the object itself before money and prestige are committed.
  3. Authenticate by measuring intrinsic properties a faker cannot mimic — here, the alloy's elemental fingerprint — rather than surface appearances a modern object can reproduce.
  4. Recognize that built-in disclaimers and hidden marks only protect against deception if someone is motivated to look; accepted status suppresses the very scrutiny that would reveal them.
  5. Watch for the moment when reputation makes truth costly; the longer a fake is publicly honored, the harder it becomes for those who know to correct it.

References