\section{To Unknown, 1779}

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DATE:& 1779 (?)\\
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FROM:& BF (Passi)\\
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TO:& Unknown \\
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PBF:& 31:311ff  \\
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\begin{Intro}
1779 is a best guess as to when BF wrote these instructions. It is equally unclear to whom he wrote them.
\end{Intro}

\textit{Some Directions for the Drawing out the Tone from the Glasses of the Armonica}

The Glasses must be always kept perfectly clean from the least Greasiness; therefore suffer no body to touch them with unwash'd Hands; for even the common slight natural Greasiness of the Skin rubb'd on them will prevent their Sounding for a long time. You must be provided with a Bottle of Rain Water (Spring Water is generally too hard and produces a harsh Tone) and a middling Spunge in a little Slop Bowl, in which you must keep so much of the Water, that the Spunge may be always very wet.

In a Tea Cup keep also ready some fine scrap'd Chalk, free from Grit, to be us'd on Occasion. Before you sit down to play, the Fingers should be well wash'd with Soap and Water, and the Soap well rins'd off. The Fingers when you begin to play,

not only be wet on the Surface, but the Skin a little soak'd, which is readily done by pressing them hard a few Times in the Spunge. The first Thing after setting the Glasses in Motion, is to pass the Spunge slowly along from the biggest Glass to the smallest, suffering it to rest on each Glass during at least one Revolution of the Glasses, whereby they will all be made moderately wet. If too much Water is left on them they will not sound so readily-
If the Instrument is near a Window let the Window be shut, or the Curtain drawn, as Wind or Sunshine on the Glasses dries them too fast.

When these Particulars are all attended to \& the Directions observ'd, the Tone comes forth finely with the slightest Pressure of the Fingers imaginable, and you swell it at pleasure by adding a little more Pressure, no Instrument affording more Shades, if one may so speak, of the Forte \& Piano.

One Wetting with the Spunge will serve for a Piece of Music twice as long as Handel's Water pice, unless the Air be uncommonly drying\EmDash{}

But a number of thin Slices of Spunge plac'd side by side, and their Ends held fast between two Strips of Wood like Rulers, of a length equal to the Glasses, and plac'd so that the loose Ends of the Spunges may touch the Glasses behind, and by that means keep them constantly wet, is very convenient where one proposes to play a long time. The Spunges being properly wetted, will supply the Glasses sufficiently a whole Evening, and touching the Glasses lightly do not in the least hurt the Sound\EmDash{}

The Powder of Chalk is useful two Ways.

The Fingers after much Playing sometimes begin to draw out a Tone less smooth and soft, and you feel as well as hear a small Degree of Harshness. In that Case, if you dip the Ends of your wet fingers in the Chalk so as to take up a little, and rub the same well on the Skin, it will immediately recover the smoothness of Tone desired.

And if the Glasses have been sullied by Handling, or the Fingers not being just wash'd have some little Greasiness on them, so that the Sounds can easily be produc'd, Chalk so us'd, will
clean both Glasses \& Fingers, and the Sounds will come out to your Wish.

A little Practice will make all this familiar, and you will also find by Trials, what Part of the Fingers most readily produces the Sound from particular Glasses, and whether they require to be touch'd on the Edge chiefly, or a little more on the Side, as different Glasses require a different Touch, some pretty full on the flat Side of the Brim to bring out the best Tone, others more on the Edge, and some of the largest may need the Touch of Two Fingers at once.

