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Keywords from Image Description:
postcard postcards linen castalia castalia ohio castaliaohio ohio blue hole bluehole the blue hole thebluehole c.t. art colortone ctartcolortone curteich curt teich co. curtteichco curteichchicago curteichchicago unused unknown date unknowndate entrances entrance r.e. tremper sales co. retrempersalesco date unknown dateunknown ohio