In January, 1927, soon after my return from an exploring expedition in Peru under the Chicago (then Field) Natural History Museum, I arranged with Dean Frank H. Probert of the University of California College of Mining for quantitative analysis of samples from 17 specimens of ancient Peruvian metal objects selected by me from the Max Uhle collections in the University's Museum of Anthropology. Professor Walter S. Morley kindly undertook to make the analyses in person. On February 26, the last of the specimens were returned to the Museum, and soon after that Professor Morley turned over to me a typewritten sheet giving the proportions, to a hundredth of a per cent, of copper, tin, antimony, arsenic, zinc, lead, gold, silver, and silica or insoluble materials determined.

I filed the sheet, but when next I went to use it, it could not be found. Neither Morley nor Probert any longer possessed a copy by then, and both of them have since died.