9 Pounder Bucket Identification

[rob love]

While browsing through photos of 9 pounders on the net, I ran across the attached photo of a 9pdr in Gagetown museum. There is an oval pail with lid in the photo that looks familiar to me, but, personally, I thought they were a field kitchen accessory rather than an artillery accessory. But I am ready to learn otherwise. Does anyone recognize the pail and can they identify the actual use. I have a couple of nice minty ones I got from my favorite scrapyard, and perhaps rather than simply holding parts in the shed, they can be redirected to a more meaningful existence.