“I have delayed writing to you,” Jacqueline says, addressing her sister, 9 “because I wished to tell to you at length of the interview of M. Descartes and my brother, and I had no leisure yesterday to say that on the evening of Sunday last M. Habert 10 came, accompanied by M. de Montigny, a gentleman of Brittany, with the view of letting me know, in the absence of my brother, who was at church, that M. Descartes, his compatriot and good friend, had expressed a strong desire to see my brother, for the sake of the great esteem in which both he and my father were everywhere held, and that he begged to be allowed to wait upon him next day at nine o’clock in the morning, if this would not inconvenience him, whom he knew to be an invalid. page 40When M. de Montigny proposed this, I felt hindered from giving a definite answer, because I knew that my brother was reluctant to force himself to conversation, especially in the morning. Nevertheless, I did not think it right to refuse, so we arranged that he should come at half-past ten next day. Along with M. Habert and M. de Montigny there were also a young man in the dress of a priest, whom I did not know, M. de Montigny’s son, and two or three other young people. M. de Roberval, whom my brother had informed of the intended visit, was also present. After some civilities, talk fell upon the instrument [probably that which Pascal had used in the experiments], which was very much admired, while M. de Roberval showed it. Then they spoke of the idea of a vacuum; and M. Descartes, on hearing of the experiments, and being asked what he thought was within the tube (*dans la seringue*), said with great seriousness that it was some subtle matter, to which my brother replied what he could. M. Roberval, believing that my brother had difficulty in speaking, took up the reply to M. Descartes with some heat, yet with perfect civility. M. Descartes answered with some harshness that he would talk to my brother as much as he wished, because he spoke with reason, but not to any one who spoke with prejudice. Thereupon, finding from his watch it was mid-day, he rose, being engaged to dine at the Faubourg Saint Germain. M. Roberval also rose, in such a way that M. Descartes conducted him to a carriage, where the two were alone, and battled at one another more strongly than playfully, as M. Roberval, who returned here after dinner, told us. . . . I have forgotten to tell you that M. Descartes, annoyed at seeing so little of my brother, promised to return next day at eight o’clock. . . . He desired this, partly to consult regarding my brother’s illness, as to which, however, he did not communicate anything of importance, only he counselled him to remain in bed every day as long as he could till he was tired, and to take plenty of soup. They spoke of many other things, for he was here till eleven o’clock, but I cannot tell you more particularly what they said, as I was not present on this occasion. We were prevented during page 41the whole day from making him take his early bath. He had found it give him a little headache, but that was because he had taken it too late; and I believe the bleeding at the foot on Sunday had done him good, for on Monday he conversed freely and strongly all day—in the morning with M. Descartes, and after dinner with M. de Roberval, with whom he argued for a long time on many things, both belonging to theology and physics, and yet he took no further harm than perspiring much, and slept rather sound during the night.”
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