E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Soldiers. In 1745 a soldier, quartered at Derby, was desired by the landlord to call on him whenever he passed that way, for, added Boniface, I consider soldiers the pillars of the state. When the rebellion was put down, it so happened that the same regiment was quartered in Derby, and the soldier called on his old host, but was very coldly and somewhat uncivilly received. The soldier reminded Boniface of what he said at partingI consider soldiers the pillars of the state. Did I say so? said mine host, Well, I meant cater-pillars.