LOC's Public Domain Archive
The objects in this archive are from Library of Congress - the nation’s first established cultural institution and the largest library in the world, with millions of items including books, recordings, photographs, maps and manuscripts in its collections. The Library provides Congress, the federal government and the American people with a rich, diverse and enduring source of knowledge to inform, inspire and engage them and support their intellectual and creative endeavors.
Disclaimer: A work of the Library of Congress is "a work prepared by an officer or employee" of the federal government "as part of that person's official duties." In general, under section 105 of the Copyright Act, such works are not entitled to domestic copyright protection under U.S. law and are therefore in the public domain. This website is developed as a part of the world's largest public domain archive, PICRYL.com, and not developed or endorsed by the Library of Congress, https://www.picryl.com
![[Illustration demonstrating that the efficiency of a power cycle depends on the temperature in an engine]](https://cache.getarchive.net/Prod/thumb/cdn18/L3Bob3RvLzIwMTkvMTEvMjAvaWxsdXN0cmF0aW9uLWRlbW9uc3RyYXRpbmctdGhhdC10aGUtZWZmaWNpZW5jeS1vZi1hLXBvd2VyLWN5Y2xlLWRlcGVuZHMtb24tZGNhYWZiLTEwMjQuanBn/40/50/webp "[Illustration demonstrating that the efficiency of a power cycle depends on the temperature in an engine]")