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Organ Pipes with Manometric Flames (Koenig)

Koenig Acoustical · Physics

Five rectangular open organ pipes, four of which have fittings midway along the side for flame mechanism (the fifth’s fitting is missing). Each pipe, except 716.1, has a wooden attachment near the manometric fitting which consists of a wooden bar holding a wooden tube that extends beyond the width of the pipe. At the base of each pipe is a round foot. The two largest pipes (716.1 and 716.2) have an oval opening towards the top of the pipe with a wooden door than can be slid closed, for tuning. The three smaller pipes have the torn remainder of a lead flap at their open end, perhaps to be used for the same purpose. These pipes represent the tones: Ut3 (716.1 and 716.2), Mi3, Sol3 and Ut4

These pipes may have originally belonged to either a group of five or nine pipes.

Accession Number:

Alternative Name:

Apparatus for compounding and comparing the vibrations of two air columns

Primary Materials:

Wood: Pine, Mahogany; Metal: Lead, Steel


Each pipe bears a stamped label reading: “RUDOLPH KOENIG À PARIS”

Each pipe is also carved above the lip with the tone it plays: 716.1 and 716.2 read “Ut3”, 716.3 reads “Mi3”, 716.4 reads “Sol3” and 716.5 reads “Ut”.

One the base of each pipe near the foot, handwritten in ink: “215”. This number refers to this set of pipe’s entry (along with other associated instruments) in Koenig’s 1873 catalogue.

Some of the pipes have a paper sticker applied on the base, near the foot, with a handwritten number:
716.1 reads: “PHY 1 – S”, 716.2 reads “PHY 1 kk” and 716.4 reads: “PHY 1 hhh”. This may refer to an entry in an earlier catalogue system.

Dimensions (cm):


Manometric pipes are designed to enable sound to be visualised via a gas-fired flame. These pipes are intended to be used with bunsen burners, a stand, a windchest and a rotating mirror. The mirror, when turned, enables a viewer to perceive the modulations in the flame that would otherwise be invisible to the naked eye.

According to “Altered Sensations” by David Pantalony (New York: Springer, 2009), “A thin membrane divided the capsule into two parts: one part was open to the sound vibrations under study; the other was closed to a flow of gas that came in through an input and exited through a gas jet, which was lit creating a tiny candle-sized flame. The membrane picked up vibrations in the air and transferred these vibrations to the gas, which caused the flame to flicker.” (pg 317).

With multiple pipes, the system allowed the comparison of tones:

“Both pipes rested vertically in a wind-chest and each had a capsule attached to the middle of the pipe. Each capsule had a rubber gas input tube and an output tube that connected to a stand for the burners, which were placed one on top of the other. A rotating mirror sat adjacent to the stand in order to pick up the signal from the burners. Two ut3 pipes, for example, displayed identical flame signals. Other combinations demonstrated the differences between octaves, thirds, fifths, etc.” (Pantalony, pg 319).


Good. All the pipes have some wear on the edges and corners. Some of the pipes are missing part of their manometric flame fitting. 716.1 is missing its entire fitting and also the wooden attachment. It is possible that these parts were deliberately removed for reproduction. The original lead covers of three smaller pipes are broken off.

Associated Instruments:,,

Manufacturer: Rudolph Koenig, Paris

Date of Manufacture: c.1878


These pipes are part of a collection of acoustic teaching apparatus purchased from Rudolph Koenig by University of Toronto professor of physics James Loudon. These pipes were probably part of Loudon’s initial 1878 purchase, and form part of a comprehensive selection of organ pipes “representing a… demonstration of every possible organ pipe effect.” (Pantalony, Altered Sensations. New York: Springer, 2009. Pg 119-122). These were likely used by students for investigations of acoustical properties at the university’s physics department teaching laboratory.

Additional Information and References:

The windchest, a gas stand, and rotating mirror that were apparently purchased as a set with these pipes (as they all carry the marking Koenig catalogue “215”) have been accessioned separately as they were also used with other pipes.

Rotating Mirror:
Gas stand:

These pipes were originally given separate accession numbers. When re-catalogued together, a document was created that provides information on original accession numbers and other transition information. This document is stored in UTSIC’s Google Drive folder.

See also, “Altered Sensations” by David Pantalony (New York: Springer, 2009) pgs 317-320.

For an example of the visualisation of a flame in a rotating mirror: [Accessed: 10/09/2016]

Historical Notes: