seems likely

You might find this web site useful= it mentions the use of dowels in the construction of the pedals
http://www.concertpitchpiano.com/GrandPianoConstruction.html

It's the holes you put your tuner in to tune, I think.
http://www.google.com/search?hl=en&sa=X&oi=spell&resnum=0&ct...

Like you, my first reaction was that they were referring to the tuning pins (tuning pegs). However, in looking for confirmation of that idea, I found that the "tourillon" of a violin was the sound post. While not all grand pianos have sound posts, historically, there are a few that do use one or more sound posts and they are also used to adjust the sound of some pianos that have sound problems. In addition to these two possible translations, there is also the bridge pin. Note also that some pianos use agraffes instead of bridge pins.

L'âme est un tourillon en sapin dont la position donne la couleur de la sonorité au violon. Plus on l'éloigne du chevalet plus le son sera clair.
http://www.galeriemusique.com/index.php?page=instrument&id=4...

View of a sound post through the end pin hole at the bottom of the violin. Also seen are some of the cleats which reinforce the back seam.
The sound post is a small dowel of Spruce that is held by friction between the top and back plates of a violin (viola, cello, or string bass), situated under the treble side of the bridge. It has both structural and tonal importance.
Structurally, it supports the top plate, acting like a pillar under the bridge. Without it, a violin would "cave in" on the treble side. A good violin, however, may not be harmed if it is without a sound post for a short period of time, but an instrument should not be left in this situation for long.
Acoustically, the sound post transfers vibrations from the top plate to the back plate of the instrument. It also alters the vibration of the top plate. Its placement, length, thickness, grain orientation, and wood selection influence the tone of an instrument. An instrument without a sound post will sound weak, thin and hollow.
On the bass side of an instrument is a "bass bar", a cross section of which can be seen in the illustration above. It has both acoustic and structural roles as well.
http://www.violins.on.ca/luthier/soundpost.html

sound post. in the violin family, a small wooden piece wedged between the front and the back.
soundboard. the resonating board of a piano which also serves as the anchor for the strings.
http://www.basmacioglu.com/index.php?dir=dict&text=S
In a string instrument, the sound post is a small dowel inside the instrument under the treble end of the bridge, spanning the space between the top and back plates and held in place by friction. It serves as a structural support for an archtop instrument, transfers sound from the top plate to the back plate and alters the tone of the instrument by changing the vibrational modes of the plates.
The sound post is sometimes referred to as the ame, a French word meaning "soul". The bow has also been referred to as the soul of these instruments. The Italians use the same term, anima, for this.
Sound posts are used:
• In all members of the violin family;
• In some members of the viol family;
• In some archtop guitars;
**and in other string instruments.**
http://en.wikipedia.org/wiki/Sound_post
1783 ----John Broadwood introduces the sustaining pedal, replacing the knee lever. He receives patents for scale designs incorporating two or more soundboards in the same piano, and for a **soundboard with sound-post** (bridge).
http://www.mathispiano.com/technol.htm

783 (Eng. 1379) Broadwood, John ( 900 ). SOUND-BOARD - with sound post or connecting Bridge : Two sound boards. The upper one connected by a sound post to the lower board which is about one inch from the bottom of the instrument.

1842 (Aust. ) Pottje, Johann ( 903 ). SOUND-BOARD - with **sound post** or connecting Bridge : two sound boards with connecting bridge. See under SOUNDBOARDS Two in connection with one set of strings.'
…
1843 (Am. 3045) Hews, George; March, C; Tileston, N. ( 881 ). SOUND-BOARD - Two or more in connection with one set of strings : Secondary or sub-sounding board to be arranged below the ordinary one. Rectangular in shape and may have holes in it to allow the air to circulate freely. One or more **sounding posts** of the same wood as the upper board may be used to connect the two boards.
http://www.geocities.com/threesixesinarow/hardingpat.htm

One trick which may help you is to place a dowel
>between a back beam and the sound board, placing
>it at a strategic distance to reduce soundboard
>activity some, but not too much. I've done this
>several times to help a cross-over which is
>uneven. It becomes a piano with a sound-post but it works.
http://www.ptg.org/pipermail/caut/2006-August/019395.html

A vibrating string on its own makes only a very quiet sound, so string instruments are usually constructed in such a way that this sound is coupled to a hollow resonating chamber, a sounding board, or both. On the violin, for example, the taut strings pass over a bridge resting on a hollow box. The strings' vibrations are distributed via the bridge and soundpost to all surfaces of the instrument, and are thus made louder. The correct technical explanation is that they allow a better match to the acoustic impedance of the air.
It is sometimes said that the sounding board or soundbox "amplifies" the sound of the strings. Technically speaking, no amplification occurs, because all of the energy to produce sound comes from the vibrating string. What really happens is that the sounding board of the instrument provides a larger surface area to create sound waves than that of the string. A larger vibrating surface moves more air, hence produces a louder sound.
http://en.wikipedia.org/wiki/String_instrument

Locate the **tuning peg** for the string in question and place the hammer on it. The principals of proper technique are beyond the scope of this article, but the basic idea is that you must listen for oscillation or beating between the notes. Just like with a guitar, the slower the beats, the closer the pitches are in tune.
http://www.doghousenyc.com/articles/piano_tuning.php

Each piano has thousands of intricate moving parts and a complex system of 250 or more high-tensile-strength steel strings, pulled across an iron harp that holds 40 tons of string tension! Each string is wound around a **tuning pin** that is driven into a wood pin block. The pins must fit very snug in order to hold the tension. In piano tuning, these pins must be carefully rotated one at a time to change the pitch of each accompanying string. This is done with a tuning hammer and requires a great amount of carefully applied strength.
http://www.wisegeek.com/what-is-piano-tuning.htm

Bridge pins are used on some musical instruments to locate the string precisely in the horizontal plane and to affect the sustain of the strings. They are usually made of steel in modern pianos, of brass in harpsichords. The sustain control function of a bridge pin is not needed in modern pianos since the tuning of multiple strings with the same pitch is used to control sustain, however it is crucial to the sustain of harpsichord strings which sound singly.
http://en.wikipedia.org/wiki/Bridge_pin

The Stuart and Sons piano company of Newcastle, New South Wales, Australia makes a piano in which there are bridge agraffes. Agraffes are kind of sturdy metal clip that hold the strings in place. They were invented in 1808 by the piano pioneer Sébastien Érard and have long been employed in quality pianos to terminate the front, that is closer to the player, end of the string. The American company, Sohmer, along with Bluthner in Europe, among others, applied this idea to the string termination on the bridge in pianos, beginning in the 1890s, where bridge pins are ordinarily used. **Most applications of agraffes have been located at the near end of the strings, close to the ***tuning pins.*** Stuart has reintroduced the use of agraffes on the bridges (of which their pianos have two).
http://en.wikipedia.org/wiki/Innovations_in_the_piano

The traditional method for constructing the string bearing point on the bridge is a notch in the wood with two metal pins, which form a sort of horizontal zig-zag clamp, holding the string against the wooden bridge.
Typical metal bridge pins on a wooden bridge (bass bridge of an August Förster concert grand). [click on the thumbnails to see larger pictures]
…A bridge agraffe is a metal device which couples the strings to the wooden bridge. It has been made in various shapes, but all have several features in common: …
http://calin.haos.ro/c/instruments/bridge_agraffes/index.htm