Beck certainly loves his loops.  The bass line is basically the same 
throughout, although he alternates the ending of the 4th bar.  These
are the 4 main variations.



G|----------------|----------------|----------------|----------------|
D|----------------|----------------|-------2-2/12---|-12-10-8--------|
A|-----2-3-5------|----2-3-5-------|-3--------------|----------------|
E|-3--3-----------|3---------------|----3-----------|----------------|



G|----------------|----------------|----------------|---5--4--2------|
D|----------------|----------------|-------2--5-----|----------------|
A|-----2-3-5------|----2-3-5-------|-3--------------|----------------|
E|-3--3-----------|3---------------|----3-----------|----------------|


G|----------------|----------------|----------------|----5  /7-5-4---|
D|----------------|----------------|-------2--5-----|----------------|
A|-----2-3-5------|----2-3-5-------|-3--------------|----------------|
E|-3--3-----------|3---------------|----3-----------|----------------|


G|----------------|----------------|----------------|----------------|
D|----------------|----------------|--------2-2/12--|---12--12--14---|
A|-----2-3-5------|----2-3-5-------|-3--------------|----------------|
E|-3--3-----------|3---------------|----3-----------|----------------|