I wonder if you can help me with a query on this wonderful song.

In one of the verses it says "his legs and his irons have all gone to decay". Now, the mention of "legs" in this line seems a little out of place, since the following line mentions "Likewise his poor old body etc". In other words, it would be more "neat" to my thinking if the first line refers to equipment/dress and the second to elements of the body. The way it stands the two are mixed, unless...

...is perchance the expression "legs" significant of some item among the horses tackle? Do you happen to know anything about this? Or am I just being super-finicky?

I'd be grateful for your views