Martingale System

6th July. Smash and grab. Not many tables going above 4 streaks, so started at 5. One player had $800 on black with my $25. Lost that. I put down on another table on a last 18. Lost. My double on the black hit, along with the other player who had gone to $1k. My double on the last 18 hit too. 15mins. Hourly rate $200.