American Memory:  Technical summary

Evolution of the Conservation Movement, 1850-1920

Collection Overview

Multiformat collection of selected materials that documents the historical formation and cultural foundations of the movement to conserve and protect America's natural heritage. The conservation movement is seen through the wide lens of cultural history, and includes both the essential documents of conservationism itself--its major philosophical statements, for example, and its legislative landmarks--and works that represent the most important facets of conservationism's generative cultural milieu, such as the literature of scenic tourism, or of popular ornithology. For the same reason, we have designed the collection to reflect as closely as possible a historically accurate balance among the perspectives of different social classes and geographic regions, between public and private initiatives and between state and Federal leadership, and to attend appropriately to chronology by including seminal works and first editions whenever possible. In the second place, the collection has been developed in order to replicate for users in the electronic environment something of the experience of research in the Library of Congress itself. Accordingly, the collection's structure retains distinctive attributes of the Library's custodial structure, and its editorial apparatus is intended to provide the kind of archival and contextual guidance that might be offered by an informed and helpful reference librarian with subject expertise in the scholarship of American environmental history and intimate familiarity with the materials in her care, while leaving users largely free to form their own analyses, judgments and interpretive conclusions about the documents they find.
Source collection (for original materials)
Technical features
Varied materials in many formats that bear on the same broad topics or themes, requiring intellectual effort to tie the threads together; extensive searchable text for books; extensive federal legal documents in page image-form that would benefit from searchability; historical materials for which one could draw strong parallels with topics found in other, non-Library of Congress resources.
Original material formats
Number of original items
793 (60 books and pamphlets, 140 Federal statutes and Congressional resolutions, 34 additional legislative documents, 23 excerpts from the Congressional Globe and the Congressional Record, 360 Presidential proclamations, 172 prints and photographs, 3 historic manuscripts, and a two-part motion picture.)
Status of collection
Available online.
Public access:
The Library is not aware of any U.S. copyright or any other restrictions for the documents in this collection. See notes on rights and restrictions provided by the Library to users of this collection.

Aids to intellectual access

Type & granularity
MARC bibliographic records. Bib. records typically describe a single item, which may be represented by multiple files.
Sample bibliographic display in American Memory.
Linking to digital reproductions
Bibliographic record contains identifier used in names for directories (for documents) or files (for other formats). Numbering system in place to link searchable text to page images and illustration images. [Sample directory for document converted to searchable text.] Numbering system and page-turning dataset in place to sequence and present page-images for documents reproduced only as images. [Sample directory for document converted only to page-images.] Multisegment motion picture filenames end "s1," "s2" to indicate segmentation; identifiers for each segment also appear in bib record.

Digital reproductions

Total file-space for digital reproductions: 2 Gbytes

Types of material: [Documents (searchable text)] [Documents (page-images only)] [Pictorial images] [Motion pictures]

(searchable text + page-images)
Archival text file Page images Printing version images for illustrations
Marker Filename extension ".sgm" Filename no hyphen Filename includes hyphen
Formats SGML TIFF Group IV TIFF or PCX
DTD American Memory
(TEI conformant)
n/a n/a
Tonal resolution n/a 1 bit 1 bit
Spatial resolution
n/a 300 dpi 300 dpi (random-pattern dithering)
Quantity (approx) 49 11,000 (approx) 1,500 (approx)
File size 30-2,100 Kbytes 40-80 Kbytes 10-200 Kbytes
Sample Sample SGML document Sample page-image Sample illustration

(page-images only)
Archival page images (printing quality) Service page images (page-turning)
Marker Filename extension ".tif" Filename extension ".gif"
Formats TIFF Group IV GIF
Tonal resolution 1 bit 4 bit
Spatial resolution
300 dpi 50 dpi
Quantity (approx) 5,000 pages 5,000 pages
File size 20-50 Kbytes 10-40 Kbytes
Samples Sample printing Sample page-turning

Photographs Archival image Service image Inline thumbnail Additional thumbnail
Marker Filename ends "u.tif" Filename ends "r.jpg" Filename ends "t.gif" Filename ends "t.tif"
Tonal resolution (grayscale) 8 bit 8 bit 8 bit 8 bit
Tonal resolution (color) 24 bit 24 bit 8 bit 8 bit
Spatial resolution (approx) 1024x768 pixels
(some 1200x1000)
1024x768 pixels
(some 1200x1000)
150x100 pixels 150x100 pixels
Quantity (approx) 29 172 172 166
File size (grayscale) 2-4 Mbytes 30-260 Kbytes 13-20 Kbytes 20-30 Kbytes
File size (color) 5-7 Mbytes 50-130 Kbytes 15-18 Kbytes 25-35 Kbytes
Sample Sample archival Sample service Sample thumbnail Sample thumbnail

Motion Pictures Service file Service file Inline thumbnail
(still image)
Marker Filename extension ".mpg" Filename extension ".mov" Filename ends "t"
Formats MPEG-1 QuickTime GIF
Data rate ca. 1.2 Mbits/sec ca. 640 Kbits/sec 8 bit
Image size 320x240 pixels 160x120 pixels 300x100 pixels
Frame rate 30 fps 10-15 fps n/a
Color depth n/a 24 bits 8 bits
File size 22-31 Mbytes 11-17 Mbytes 90 Kbytes
Quantity 1 movie 1 movie not yet available
Sample Sample MPEG Sample QuickTime N/A

Library of Congress contribution to Digital Libraries Initiative - Phase II [Site Map]
Collections: [List] [Rights] [Samples] [Handover]
Technical notes: [Documents] [Images] [Maps] [Sound Recordings] [Motion Pictures]