First guess Len, a drastic disruption. We'd suppose the two 110-v lines to be out of phase so the diff is 240 v. Sounds like L1 has shorted to ground while the neutral has become ungrounded
Complete gibberish; on a properly configured system, Line One and Line Two are always 18o degrees out of phase on a 120/240 single phase three wire system, and it's series aiding not "the diff is 240 v".
As to your claim of a so-called "a drastic disruption" that level of insight into power distribution troubleshooting is simply laughable. Again I could reference many more including bonding and grounding and circuit protection and ground fault requirements as per the Code, but I'm betting you have no clue so any further input I might provide would be hazardous to the OP's health and yours too if you think you know what you are talking about.