I cannot convey to you the distress of your household in learning of your accident, which arrived today by a messenger from the Palais-Royal. I wept when he informed me of your grave state of health and more bitterly so that I had no means of assisting you in your distress. Upon receiving this news I made plans to return immediately to the rue de Miromesnil, where I currently reside. I have requested that the messenger, who you will be surprised and pleased to learn is none other than Our Friend, dispatch to me a regular account of your condition. He has promised to deliver this in person, whenever the occasion permits. Dear Madam, I shall make daily prayers for your recovery and think of nothing else until it is achieved.

Orléans had called upon Mrs Elliot. I straightened myself in my chair. I had hoped but not imagined that my entreaties to him would have yielded such success. Encouraged by what I had read, I hastened to open the next letter, which I discovered to be written in a curious fashion. There were but a few lines penned on an otherwise blank sheet.

Madam, today the messenger delivered the confirmation of your recovery for which we have long prayed. All the household sighed and wept to hear of it. That you shall not be taken from us is a blessing indeed, for which I sign myself ever grateful,

Thérèse Bertrand

P.S. Madam, I mean not to trouble you further, but with regard to the paper you bid me purchase, I would beg you to examine the watermark upon this sheet and instruct me as to the quantity you require of it.

I furrowed my brow and read the words once more. Most of Mrs Elliot’s references were not so obscure as this one. Purchase of paper? I puzzled. I could not conjecture her meaning. Greatly bemused, I held the letter to a candle in search of its stamp. It was then I saw it.

As I held the paper near to the flame, I beheld no watermark upon it, but rather faint, browning sentences. As the heat took them they emerged through the grain. I could scarcely believe it, but as I moved the sheet about before the candle, an entire secret letter penned in an invisible ink materialized in my hands.

‘My dear Henrietta,’ the salutation burned itself upon the page:

Late events have now rendered it necessary for me to resort to a more clandestine method of correspondence. My home on the rue de Miromesnil is now subject to frequent searches by the guards who harass me with such regularity that when the barriers open, I intend to make for my house at Meudon once more.