Starting a fire using the bow drill method is an art form in itself and it takes a lot of practice to have a high success rate. I have successfully managed this only a few times under controlled conditions. I hope that I will never have to resort to this method in a survival situation where the conditions are not idea...and this why I always carry multiple methods of fire starting; wooden matches, BIC lighter, firesteel.
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Earth and sky, woods and fields, lakes and rivers, the mountain and the sea, are excellent schoolmasters, and teach some of us more than we can ever learn from books.

John Lubbock