The Indianapolis Switch & Frog Co., 25-Nov-19. A letter from the Indianapolis Switch & Frog Co. to the Maintenance Official of Manchester St. RY (Rail yard) in Manchester, NH, promoting their new high speed mounting device for their Portable Electric Welder. This 'mounting device' was essentially a new trailer for the welder to sit on. This new trailer was slimmer and went from a four wheels to two wheels. The letter itself appears to have been a generic letter send out to advertise the new device with the Manchester St. Rail Yard filled in . Accompanying the letter are three photographic images of the mounting device printed on a single sheet of photographic paper. The top photograph depicts the Portable Electric Welder on its original mounting device with the new one next to it with the caption "Ready to Remount". The middle photograph depicts the welder on its new mounting device, and the older four wheeled trailer now empty beside it with the caption "30 minutes later, Remounted". The bottom photograph is a close up of the new mounting device with the welder on it, with the caption "Heavy Duty High Speed Outfit". Measures 10 3/4" x 8 1/4" (letter), 10" x 7 1/2" (photograph). General wear. Small cut on left edge of photograph.