which links to https://lccn.loc.gov/00694271 , but that does not seem to have a digital copy available
edit: well here's an archive but it's not any better https://web.archive.org/web/20231016184047if_/http://memory....
7m20s of the same video clip features a clip shot of riders on the overhead converyor/walkway.
[the original film was silent, audio is faked]