CREATE TABLE table_30839 ("By-election" FLOAT, "Electorate" CLOB, "Date" CLOB, "Incumbent" CLOB, "Reason" CLOB, "Winner" CLOB)

When james seaton is the incumbent what is the reason?
SELECT "Reason" FROM table_30839 WHERE "Incumbent" = 'James Seaton'
SELECT "Reason" FROM "table_30839" WHERE "Incumbent" = 'James Seaton'