E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Hard terms; rather rough treatment; exacting. Lines mean lot or allotment (measured out by a line measure), as, The lines have fallen to me in pleasant places; yea, I have a goodly heritage, i.e. my allotment is excellent. Hard lines = an unfavourable allotment (or task).
That was hard lines upon me, after I had given up everything.G. Eliot.