How to make glass?

How many glass bottles do I need to make a glass music instrument that covers two octaves?

• How much water do i have to put in each bottle to make the two octaves with sharps and flats? What's the best kind of way to make a leak-proof cover for the bottles? What size should the bottles be?

• Answer:

  You need twenty-four. Each octave consists of 5 notes with their corresponding sharp plus 2 without, amounting to 12 notes. For example, C-scale: C, C#, D, D#, E, F, F#, G, G#, A, A#, B. If you want two octaves, double that. A twenty-fifth bottle is needed if you want the third major note (here, the high C). Try using glass soda bottles or Perrier if you're splurging, but they all should be the same kind to make it easier. And if you find ones with twist-off tops, obviously that would be nice for stopping leaks.