content: Having gone through the first 3 chapters of this book, I must say I am really dissapointed. The author is supposedly trying to avoid the mathematical rigor to the account of explaining things in a physical way. Well, he almost completely fails in that and, the worst, confuses the reader. For example, he devotes 15 pages to smoothly introduce the reader to the concept of a manifold, promising a more rigorous definition to be given later on. When the time comes, he uses two "brand new" concepts, namely Haussdorf space and countable base, for the meaning of which, the reader has to look up in other books!(however cited in bibliography) If one wants to understand what all these things (manifolds, diff. forms, Lie deriv, etc.) are about, the best thing to do is buy a mathematical book. After all, it is hardly possible to satisfactorily describe abstract mathematical concepts if you avoid using mathematical language! For the interested, I am NOT a mathematician.