Oil-Jacks

Oil Pump Jacks in the US. Source: Richard Masoner / Cyclelicious via Flickr ( https://flic.kr/p/5NFhTB ). License: CC BY-SA 2.0 ( https://creativecommons.org/licenses/by-sa/2.0/ ).

Oil Pump Jacks in the US. Source: Richard Masoner / Cyclelicious via Flickr ( https://flic.kr/p/5NFhTB ). License: CC BY-SA 2.0 ( https://creativecommons.org/licenses/by-sa/2.0/ ).