They are a staple of the railroads, doing yoeman's duty in the harsh months of winter. Coupled in front of an engine at one time it would have been steam, both engine and crew would set off for wild ride down the track of perhaps some particular sub division that had had a heavy snow fall. Ramping up to a decent, both plow & engine would speed down the track slamming into snow banks that had collected in pockets along the line, at crossings, gully's where snow collects, etc driving ahead to purge the tracks and switches of snow. A valued lesson was never stand by a level crossing when the plow comes along as you can be buried pretty quickly by the cast off snow that it fires out as it rockets past doing its duty and keeping the tracks clear.......thanks for the peek.