Want to be a treasure finder? Apparently you need a device to clearly see an old map. Take a look the iPhone 4 microscope that might meet your need.
The iPhone 4 microscope features a dual-tube style. One tube is a tiny 60x microscope with a lens cover with adapter, another comes with three LED lights, one of them is note detector LED for watching the water mark of the paper note. Apart from that, the iPhone 4 microscope measures 3.7 x 4.1 x 1.7 cm, and need 3 LR1130 batteries for power.