I loved reading Far Side as a kid. But my reaction to probably 10% of them was "I don't know if I am too dumb to get the joke or the joke is too dumb for me to recognize it as a joke."
Anyway, here's the pic alone https://upload.wikimedia.org/wikipedia/en/9/9a/Cow_Tools_car...
And here's the wiki article it's in, with explanation, such as it is https://en.wikipedia.org/wiki/Cow_Tools
Unrelated, look up the wiki article for Thagomizer. It's funny and show life following art (Q: are Larson's comics art? A: yes.)
Edit: save you the effort https://en.wikipedia.org/wiki/Thagomizer
For me this comic combined with the general limitations of what he does are what make him second to Bill Watterson. Somehow Watterson managed to be much broader and yet as far as I know there's not a single flub in any of his Calvin & Hobbes comics.