Answer:
I move without wings Between silken string I leave as you find My substance behind.
Everyone has me and no one can lose me. What am I?
I am an English word that is as long as I am valued.
It's in your hand though you can not feel it. Only you and time can reveal it.
The time between daylight and darkness when blood drinkers like to come out
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.