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Photo of Gerhard Finkenbeiner Ben Franklin's Harmonica -- Gerhard Finkenbeiner

German-born glassblower Gerhard Finkenbeiner first heard about the glass harmonica while living and working in Paris in the 1950s. Using original plans, he created a modern version of the instrument originally invented by Benjamin Franklin in 1761. Find out more about this unusual instrument and its strangely beautiful sounds by reading Finkenbeiner's answers to questions from Frontiers viewers.

Q What a wonderful sound and beautiful tone! Do you know of any recordings (CD's or tapes) of the glass harmonica? It is not mainstream so I doubt I could get it at the local store unless I request by title and artist. Thank you very much for your help.

A Thanks for your kind words and question! We have about 12 different recordings available through our website -- go to Also, Thomas Bloch/GLASSHARMONICA is available from Tower Records, Boston, and Cambridge (MA). Hope this helps and thanks for helping to promote Glass Music!

Q What is the special ingredient in the water that helps make the sound when you play the glass harmonica? How does it help create the sound?

A Thanks for your question! The "secret" ingredient is talc. This helps the fingers "grab" the glass for a more pronounced and accurate attack. People both today and in Ben Franklin's time have also used chalk, wine and grain alcohol in their glass harmonica water.

QWhat is the difference in the glass that Ben Franklin used and the glass that you use to make the modern-day glass harmonica?

A The glass I use today to make our glass harmonicas is 100% fused silica or Quartz, and contains no lead. The glass used in Franklin's time, know as "soft glass", may have had lead and certainly other materials (i.e., potash) that helped reduced its "working temperature", that is, the temp that it will begin to melt and can be formed.

Quartz produces a good sound, in many cases, even when the formed cup is not completely symmetrical, a problem that plagued cups that were made in Franklin's time. Fused silica also can withstand more intense vibrations from playing, etc., and is less easily broken than soft glass. It produces a more pronounced tone, that I obviously have come to love.

QI was wondering if playing the glass harmonica was similar to playing the piano? It looked as if the 'bowls' were laid out in a similar fashion as the keys on a piano.

A Yes, the layout and playing of a glass harmonica is similar to a keyboard instrument, with the gold bands (painted on the inside of the cups) serving as marking for the flats or sharps, like the black keys on a piano. It definitely helps a great deal in playing this instrument to have knowledge of piano, etc. The technique, however, is somewhat different, and varies greatly from person to person.

The fingerings are a marriage of keyboard and string instrument technique, as the chromatics are not physically displaced as they would be on a piano, but are instead in series along with the naturals, like a guitar or violin. One uses the edges or pads of the fingers to make a sound , as opposed to striking using the tips. Hope this helps! Thanks for helping to promote Glass Music!

QWatching you blow the glass was very interesting. How did you first become interested in glassblowing? How can I learn the art of glassblowing?

A I became interested when I was young and still living in Germany, later graduating from glass blowing school after about ten years of study. Several of these schools exist in Europe and the US.

There is a good book out called "Contemporary Lampworking" which gives a thorough introduction into glass blowing, with any of the necessary tools, etc. Available from:

Salusa Glassworks
223 N. McCormick St.
PO Box 2354
Prescott, AZ 86302

Best of luck to you!

QPlease explain to my 5th graders the purpose of the gold rims on some of the glass bowls. They want an expert explanation! Thank you.

A The gold rims serve as a marking for the accidentals (flats or sharps), much like the black keys on a piano. The gold coating is painted on the inside of the cup using a special material which bonds with the glass at a certain temperature, when baked in a glassblower's oven. It is very thin and does not affect the sound or playing when properly applied. We have made a few instruments with no gold markings. Thanks for your interest!

QFirst I would like to know if there is any way possible to get my own glass harmonica. I thought it had a beautiful sound and would love to have one.

A Thanks for your question! G. Finkenbeiner Inc., my company, manufactures and sells Quartz Glass Harmonicas. We have a listing of standard instruments on our site:

You may also write or phone:

G. Finkenbeiner Inc.
33 Rumford Ave
Waltham, MA 02154

Fax 617-647-4044

Q About how long does it take for you to make the complete instrument?

A Depending on the size of the Glass Harmonica, an average delivery time is 3 to 6 weeks, and can vary depending on the amount of orders already being filled. It may not actually take all of that time to construct the instrument, as the scientific glassware work remains fairly constant.

QWhat kinds of music is mostly played on glass harmonicas these days? Is it usually played as a solo instrument?

A The music being played on the Glass Harmonica these days is as varied as the players themselves, but seems to be mostly Classical, New Age and Colonial. It really stands out as a solo instrument, but blends well with Chamber groups, harp, organ and has also found a niche in filmscoring.

Q Do you have any other special glass instruments or unusual projects that you are working on currently that we did not see on the show?

A At this time we are not working on any new types of Glass Instruments, as the workload between the scientific glass work and the Glass Harmonica keeps us more than busy enough.

We are, however, enjoying a renewed interest in our Quartz Bells, an invention of mine which uses electronic amplification of a vibrating Quartz thread to produce amazingly bell-like sounds. Many churches in Europe and the US have had our Quartz Bell Units installed to replace heavy and expensive cast Bronze Bells.

Q I would like to see a glass harmonica. How can I find out if there are any harmonicas displayed in any museums around the country?

A The Museum of Fine Arts in Boston and the Franklin Institute in Philadelphia are two museums which house Glass Harmonicas. Others may exist that I am not personally aware of. The internet has extensive mention of Glass Harmonicas, as I have found through various search engines. This may help a great deal, as there's more info out there than I have had time to scroll through myself.

QI was wondering about how long it took you to research and create the exact replica of the harmonica Ben Franklin invented.

A In 1982, through the courtesy of Prof. Richard Weiss, I was able to obtain plans and dimensions from a period instrument housed at the Staatliches Institut fur Musikforschung in Germany. A prototype of my Quartz Glass Harmonica was completed soon after.

The instrument shown as part of our segment on Scientific American Frontiers included a replica cabinet constructed by one of our customers; Dr. Steven Lash. He was able to obtain specific dimensions from the original instrument housed in The Franklin Institute in Philadelphia, PA. around August 1994.

After his rough construction was completed, we were hired to "fill" the cabinet with a set of glasses comprising one of our Quartz Glass Harmonicas. Although the cabinet is a replica, it actually contains one of our "improved" instruments, and is motor driven.

Our instruments are based on Franklin's principle of a mechanical Glass Instrument, and use cork as a mounting for the glasses (as has been done historically) . However, our use of Quartz glass, our cup design and drive mechanism are not sold as Franklin replicas.


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.