There isn't another acoustic sound quite like the glass armonica. Here's my easy-to-make, inexpensive version.
* Glass stemware or bowls with round, smooth, non-ridged sides
(It doesn't have to be crystal.)
* Silicone adhesive
* An old platter, sturdy cookie sheet, or piece of plywood
* Permanent marker(s)
Line up your glasses on a table and tap. listen, and sort them from lowest to highest pitch. If your glassware is all from the same set, the pieces will be close in pitch, but there will be differences. (Sorting will extend your range.)
Next, fill the lowest pitched glass with an inch (or less) of water. Dip your fingers into water and firmly rub the rim of the glass at until is 'sings'. Identify the pitch this first glass produces by comparing it to another instrument or using an electronic tuner or phone app. You'll want to use the lowest note possible for your first glass so you can have a greater range, but your instrument will be more versatile if you create it in a common key such as C, G, F or D. So explore your best options for a tonic (first note of scale). If a note is flat, add some water; if it's sharp, remove some water. Once you have established your first note and its water level, mark the water level on the outside of the glass with a permanent marker and write the note name.
Pour slightly more water into the second glass than you did the first, wet your fingers, rub the rim, and then tune the note it produces to the second degree of your chosen scale (by slightly increasing or decreasing water). Mark the water level. Continue this process for subsequent glasses/notes of your scale.
Note: Different scales (major, minor, blues, pentatonic, ethnic) and neighboring keys can be achieved with the same set of glassware. If you desire this versatility, mark each tone set with a different colored marker.
Once you have your pitches marked, empty the glasses and make sure their bases are dry. Arrange your notes/glasses on the base (platter or board) in a logical order and allow adequate space between glass rims. Apply silicone adhesive to the bottom of each glass, set them in place, and allow silicone to cure for a few hours.
You can easily make larger instruments, but for classroom use and portability, a five to eight note set works well. (I lined a sturdy cardboard box with an old towel to create a case for storage and transport.)
Picture on left: Glass armonica being played in Rome, Italy.
Photo by Adrian Pingstone, Wikimedia Commons.
Link to a video of Ave Maria being played on glasses:
History of the Glass Armonica (Ben Franklin) and resources:
Link to an online, interactive glass armonica: