Illustrated Catalogue and Price List of Photographic Apparatus and Supplies, Blair Camera Co., (Boston, MA), dated 1895, ~6"x9", 52pp

In the Appendix of this 1895 catalog (page 44), we find statements that the improved versions of the Reversible Back Camera and the Cincinnati Camera are the same as the previous version except that the improved have center swing (long back hardware that has pivots at the center of the rear standard instead of short hardware that pivots at the bottom of the rear standard.  This would seem to define non-improved verses improved versions were it not for the fact that in the 1890 catalog, the same versions here called previous were already referred to as "improved" versions.  Apparently, Improved was used to describe any of a number of continual improvements. 

pages 24-43 not scanned