What are the lacish letters and when were they written

The lacish letters were discovered in 1935 (January/February). They were written on clay and recorded the defence of an army officer who had read (or not read them). They were written about the time of the seige conducted by Nebuchadnezzar. Their importance is not Biblical, but they are a comment on one aspect of life around that time (almost 600 BC)

Athe rate increases as income increases