As steam locomotives evolved over time there were occasions where one could see the very oldest active steam power posed with the newest as it entered service. The contrast in power could be very dramatic as we see in this photo.
The date is approximately 1915 and the location is Pocatello, Idaho. An early railroad photographer has set up his camera in the Union Pacific yards to capture on film the transition of steam power for it's earliest days to "modern" times. His lens was trained on a pair of Oregon Short Line locomotives spanning from the beginnings of the UP to the then present times.
On the left is venerable 4-4-0 #214 that had been turned out by the Schenectady shops in 1875 during the railroads earliest years. At the time she was looked upon as possessing the most modern refinements in steam power then available. Towering over her to her right is Baldwin's 1912 version of a big 2-8-2 in the form of OSL #1134.
Besides the obvious size difference the 2 locomotives had, the real comparison came in the form of tractive effort. #214 could only boast 16,6043s of tractive force while #1134 as capable of 45,4223s of such tractive force. Needless to say steam power on the OSL had come a long ways in the 40 years between the time the 2 locomotives were built.
Time was rapidly running out to see these 2 generations of motive power working together as occurred on this day. All too soon, #214 would turn her last mile as #1134 soldiered on until some day, she too, would be replaced by yet a newer and more modern example of Union Pacific motive power