district               vacator                                    reason for change                  successor date successor seated
0            new york 1st  jonathan havens (dr)                               died october 25 , 1799            john smith (dr)    february 27 , 1800
1  connecticut at - large    jonathan brace (f)                            resigned sometime in 1800      john cotton smith (f)    november 17 , 1800
2           virginia 13th     john marshall (f)  resigned june 7 , 1800 to become secretary of state  littleton w tazewell (dr)    november 26 , 1800
3       massachusetts 3rd      samuel lyman (f)                           resigned november 6 , 1800       ebenezer mattoon (f)     february 2 , 1801
4        pennsylvania 8th    thomas hartley (f)                              died december 21 , 1800          john stewart (dr)     february 3 , 1801

Table as JSON:
{"district":{"0":"new york 1st","1":"connecticut at - large","2":"virginia 13th","3":"massachusetts 3rd","4":"pennsylvania 8th"},"vacator":{"0":"jonathan havens (dr)","1":"jonathan brace (f)","2":"john marshall (f)","3":"samuel lyman (f)","4":"thomas hartley (f)"},"reason for change":{"0":"died october 25 , 1799","1":"resigned sometime in 1800","2":"resigned june 7 , 1800 to become secretary of state","3":"resigned november 6 , 1800","4":"died december 21 , 1800"},"successor":{"0":"john smith (dr)","1":"john cotton smith (f)","2":"littleton w tazewell (dr)","3":"ebenezer mattoon (f)","4":"john stewart (dr)"},"date successor seated":{"0":"february 27 , 1800","1":"november 17 , 1800","2":"november 26 , 1800","3":"february 2 , 1801","4":"february 3 , 1801"}}