What bad luck does Huck attribute to his having tipped over the saltcellar at breakfast one morning?

Huck blames the return of his no-good pap on
his spilling the salt. Huck is deeply superstitious, so when he knocks
over the salt he tries to quickly throw some over his left shoulder. Unfortunately, the
Widow Douglas catches him and (thinking he was merely playing with the salt) stops him
before he can throw it. Therefore, he thinks his bad luck wasn't canceled out. When he
sees the imprint of the boot heel in the snow, he knows his pap has come back, and will
soon be after his money. Thus, he turns over his money to Judge Thatcher, so his father
cannot claim it. When he returns home, his pap is waiting for him, and Huck's bad luck
begins.