I have this 1935 1$ silver certificate and it has Hawaii stamped twice on the front(small) and once on the back(large). I read that they did this during WWII in case japan seized control of Hawaii. Does anyone know when they started stamping the bills and how long the did this? It couldn't have been in 1935 as per the date on the bill. just curious about the how's and the why's. Here are some pictures Take care all.