The original sound recordings were made on 12-inch acetate discs from 1938-40. A set of master 10-inch preservation reels and 7-inch reference reels were made for the Folk Archive in the 1960s. The digital audio for Internet/World Wide Web use was produced in 1997 by A&J Recording Studios in New York City.Textual documents
Facsimiles and accuracy of transcription. The textual documents in this collection are reproduced in two ways: first, as a searchable text and, second, as a set of facsimile (page) images. The facsimile images of the documents provide the most authoritative texts. The transcriptions (searchable texts) are more than 99 percent accurate, but careful researchers will always compare the transcriptions to the facsimiles of the original documents.
Transcription and coding. In the transcriptions of text, capitalization and spelling reflect that of the original document. Where the text was illegible, bracketed question marks represent the approximate number of words that cannot be interpreted; e.g., "[???] while he [??]" means "[three unintelligible words] while he [two unintelligible words]." Where a good guess could be made, the word and a question mark have been placed in brackets, e.g., [malversation?].
When initially transcribed, these texts were marked up in Standard Generalized Markup Language (SGML). The American Memory SGML markup scheme conforms to the guidelines of the Text Encoding Initiative (TEI), the work of a consortium of scholarly institutions. Since this Internet presentation employs the conventions of the World Wide Web, the SGML markup has been simplified and reprocessed to create documents in HyperText Markup Language (HTML).
Document-image compression. The facsimile document images in this collection carry TIFF headers and employ CCITT Group 3 compression.Still photographs
The still photographs in this collection were made by Sidney Robertson Cowell, WPA staff photographers, J. L. Hall, John Bateman, and possibly others. The originals are housed variously in the Archive of Folk Culture, American Folklife Center, Library of Congress, the Music Division, Library of Congress, or in the Music Library collections at the University of California, Berkeley.
The original photographic prints were rephotographed on 35mm roll film and subsequently digitized at a resolution of about 640x480 pixels (thumbnails at about 150x150), storing 8 bits of information per pixel. The larger images are compressed using the JPEG compression algorithm.
The blueprint drawings and pencil on butcher block paper sketches were made by WPA draftsmen Jos. H. Handon, G. McCarthy, and possibly others. The originals are housed in the Music Library collections at the University of California, Berkeley.
The drawings were microfilmed at the University of California, Berkeley. Digital images were made from the microfilm; a large digital-archival image that represents the drawing in its original size and, for use in Internet and other access systems, an image reduced to print on 8.5x11-inch paper. Both sets of images are in files with TIFF headers, 1 bit per pixel, using CCITT compression.