This is an old tune found in various manuscripts, such as John Clare's 1820 and George Spencer's 1831 manuscripts. It was also in the repertoire of the Bosham Band from the Welch family manuscript. I tried playing various versions and ended up doing a bit of editing to combine parts from a couple. Its a simple tune and very catchy. A nice recording by the Gloworms got me onto it.
Here is the ABC for reference.
X:1 T:The Tank O:england M:2/4 L:1/8 K:G |:G2g2|E2e2|A2dc|BAG2|BcdB|cdec|d2f2g4:| |:B2Bc|dd|eccA|GFED|B2Bc|d2d2|ecAF|G8:|