The Laws Of Scientific Hand Reading Palmistry - Benham
The character of the Head line, which will next be considered, shows what strength there is to the mental qualities, and what ability to concentrate the mind. A deep and well cut line shows great mental power, good self control, fixedness of purpose, good memory, and general mental health and strength. There is in this case a good clear channel for the Current to flow through, consequently the ideas run evenly and smoothly - no breaks no jars, but steadiness and strength. The deep and well cut Head line shows one who is self-contained, does not "lose his head'" is not flightily or erratic, but is dignified, even tempered, evenly balanced, and has the ability to make and carry out his determinations.
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