When all else fails, read the instructions. 

Here it is, from the original libretto (end of 3rd verse): 

In short, when I've a smattering of elemental strategy, 
(Bothered for next rhyme.)--Strategy, strategy--(Struck with an idea)
You'll say a better major general has never sat a gee!

"Sat a gee" is not a made up word--"a gee" is slang for a horse: a better
major general never sat on a horse. 

--Sir Schwilliam Wank Gilbert