I believe the quote to which I responded contended that the ORIGINAL gerrymander was in the Senate. The makeup of senate seats is in the Constitution, which predates the 1889 Omnibus bill by a few years, and I'm pretty sure (although I haven't done the research) that the original states and signatories to the Constitution weren't admitted to specifically to balance slaves versus free states but instead were all separate British colonies. The ORIGINAL gerrymander got its name from Gov. Gerry, in a newspaper article that described the district that was drawn as looking like a salamander, and hence coined the term gerrymander.
I don't dispute that subsequent to the original gerrymander there have been political grounds for the drawing of state lines (all of which had nothing to do with providing representation in the senate to citizens based on the relative population of each state), but that's not gerrymandering. Pedantic thread drift over.