This is a link to a photo from the Denver Public Library:

http://digital.denverlibrary.org/cdm/singleitem/collection/p15330coll22/id/30840/rec/5

The company service boxcar is stenciled "Rotary & Water Service Material".

"Water Service" I think I understand, but what is "Rotary"?

Thanks.

Bob Chaparro

Hemet, CA