It would, therefore, be a good idea to mark the button A which is to be found on the Fundamental Bass row, third button above the countersunk C and the button Eb also to be found gn the Fundamental Bass row, third button below C. However, not to cause confusion among the Three Buttons if all are countersunk,it will be convenient to leave the C countersunk, whilst the Buttons A and Eb could be marked differently and equally easily by dropping on the said Buttons a little sealing-wax, possibly of the same shade as the buttons, so as to form a little relief on it. And so, while the C will be countersunk the A and Eb will be in relief, and in this manner any possibility of confusion will be eliminated. When the time comes, the said sealing-wax will be able to be removed, without there remaining any mark on the said Buttons. If instead one wishes to have a permanent point, one will be able to notch a little bead on the top of the said Buttons, or else to cut some mark there, always remembering,however, that the markings should be quite different from the countersinking of the C.
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