continued to circulate. Sproul, the University president, had become concerned as well. Bolton played down concerns while challenges to the plate’s authenticity were numerous and authoritative, as were demands for analysis of the relic. Journalists at home and abroad, as well as historians and archaeologists, sent requests for at least a good photograph of the plate. Bolton demurred, put off analysis, and did not follow up with experts on specific questions they had about the plate that could help determine its authenticity. A good photograph was not available even by August of 1937 when the editor of Antiquity wrote to Bolton “surely in the case of an object which, if genuine, is of the highest historical importance, at least one really adequate photograph should be made available!” Bolton chose Professor Colin Fink, chair of the Division of Electrochemistry of Columbia University, to authenticate the plate. While the California history community, and certainly Bolton, would have been aware of the Clampers' book of clues, Fink may not have been. In any case, in 1938 Fink and his colleague E. P. Polushkin confirmed the plate as genuine in no uncertain terms: "[I]t is our opinion that the brass plate examined by us is the genuine Drake Plate." For most observers, this was the definitive statement on the plate's origins. Photos of the plate appeared in textbooks. Copies were sold as souvenirs, and a copy was also displayed in the library of Sir Francis Drake High School in San Anselmo (the only high school named after the explorer). On several ceremonial occasions, copies of the plate were presented to Queen Elizabeth II. Yet rumors of E Clampus Vitus involvement in the plate continued to circulate. Scientific investigation In the early 1970s, physics caught up to Haselden's original findings. Professor James D. Hart, director of the Bancroft Library, assembled a re-testing plan in preparation for the 400th anniversary of Drake's landing. He asked the Research Laboratory for Archaeology, the History of Art at Oxford University, and the Lawrence Berkeley Laboratory for a detailed analysis. The tests included x-ray diffraction, stereo microscopy, and additional metallurgical analysis. X-ray diffraction and gamma-ray absorption tests revealed the plate to be too smooth, made by modern rolling equipment, not hammered flat by a sixteenth-century hammer. Dr. Frank Asaro, at the Lawrence Berkeley Laboratory of the University of California, Berkeley, working with colleague Helen Michels, used neutron activation analysis to