To use an expression of Madame de Sevigne, who wrote about the same time, "there was a postscript to the letter;" and the most important part of the letter was contained in the postscript.
In this postscript, William of Orange, Stadtholder of Holland, condemned Cornelius van Baerle to imprisonment for life.

He was not sufficiently guilty to suffer death, but he was too much so to be set at liberty.
Cornelius heard this clause, but, the first feeling of vexation and disappointment over, he said to himself,-- "Never mind, all this is not lost yet; there is some good in this perpetual imprisonment; Rosa will be there, and also my three bulbs of the black tulip are there." But Cornelius forgot that the Seven Provinces had seven prisons, one for each, and that the board of the prisoner is anywhere else less expensive than at the Hague, which is a capital.
His Highness, who, as it seems, did not possess the means to feed Van Baerle at the Hague, sent him to undergo his perpetual imprisonment at the fortress of Loewestein, very near Dort, but, alas! also very far from it; for Loewestein, as the geographers tell us, is situated at the point of the islet which is formed by the confluence of the Waal and the Meuse, opposite Gorcum.
Van Baerle was sufficiently versed in the history of his country to know that the celebrated Grotius was confined in that castle after the death of Barneveldt; and that the States, in their generosity to the illustrious publicist, jurist, historian, poet, and divine, had granted to him for his daily maintenance the sum of twenty-four stivers.
"I," said Van Baerle to himself, "I am worth much less than Grotius.
They will hardly give me twelve stivers, and I shall live miserably; but never mind, at all events I shall live." Then suddenly a terrible thought struck him.
"Ah!" he exclaimed, "how damp and misty that part of the country is, and the soil so bad for the tulips! And then Rosa will not be at Loewestein!".