Memorandum.

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The board need be no thicker than this one which you sent.

But its pin-holes must be a trifle bigger than the pin, so that the pin will slip in easily.

The board must be backed by a similar board (but without holes,) & between the two boards must be a layer of soft felt, half an inch thick.

Thus, each playing-board is a pin-cushion. The pin slips in quickly & easily; it buries full half of its length in the felting, & you don’t knock it out when you insert the next pin. boxed: Add this to the patent.

Apply this idea to a new experiment-board, Charley.

On the board, put neither the ‸ name of each the king, but not nor the number of years. This is surely best—for the king’s name alone tells three or four big facts.