Old Motor magazine covers

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Motor is a technical journal that caters to gas station owners, automobile repair shops, parts suppliers, and dealers. It was first published in 1903 and is still active, although it has moved from print to digital media. 

These covers are from 1904 through the 1940s. When the magazine started the covers featured a lot of women. However, they moved on to having humorous covers featuring visual jokes. Of course, during WWII they switched to patriotism and War Bond drives.

These examples are from MagazineArt, there are more at that link.