Simplex, was a manufacturing company who specialized in heavy duty jacks and tools for the industrial world. They made railroad jacks for the railroad industry. My grandfather left me two very heavy duty jacks, that would lift a house off of it's foundation. He also had one of those tools that you have pictured. What he used it for was to rig it between the rails, and pull them together to the correct distance, and spike down the rail to the wooden tie.(you would have to have something very stout to move rail obviously).You might be able to use that puller/expander tool to work in the automotive repair field. I have seen the time in my repair of a damaged frame, that a tool like that would be pretty handy to spread or pull a frame back to specs. The L&N railroad along with many roadnames used these on track gangs.Hope this helps.