Definition of "tach"

I have a rorty gal, also a knowing pal, / And merrily together we jog on, / I doesn't care a flatch, as long as I've a tach, / Some pannum for my chest, and a tog on.

c. 1864, Alfred Peck Stevens, “The Chickaleary Cove”, in Farmer, John Stephen, editor, Musa Pedestris‎, published 1896, page 161