The private life of Galileo / compiled principally from his correspondence and that of his eldest daughter, Sister Maria Celeste.

  • Galilei, Galileo, 1564-1642.
Date:
1870
Catalogue details

Licence: Public Domain Mark

Credit: The private life of Galileo / compiled principally from his correspondence and that of his eldest daughter, Sister Maria Celeste. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    51/330 (page 33)
    for the feast of St, Antony, and told me he had seen an instrument made by Sig. Santorio, with which heat and cold were measured; and at last he told me that it was a large glass bulb with a long neck. I began at once to make vessels of this description, and have succeeded in making some very handsome ones.” Sagredo goes on to say that he enclosed a drawing of the best he had made ; but, as unfortunately there is no trace of this drawing, it is impossible to say precisely what the instrument was of which Santorio was the inventor. In another letter of Sagredo, of the 9th of May, 1613, he distinctly ascribes the in- vention of the thermometer to Galileo : thus, “ The instrument which you invented for measuring heat I have brought into various convenient and perfect forms, so that the difference of temperature between two rooms is seen as far as 100 degrees.” It would appear, then, that Sagredo had been ignorant of Gali- leo’s discovery,1 and that the latter, on hearing his description of Santorio’s instrument, had proved that he had forestalled Santorio. It is# also possible, 1 Another letter of Sagredo’s confirms this supposition : “ I am j daily making alterations and additions to the instrument for measuring the temperature. . . But as you write me, and as I cer- tainly believe, that you are the first author and inventor of the instrument, I think that those which you and your exceedingly clever workman have made must be far superior to mine. Pray write and let me know how you make yours, and I will in return inform you how I make mine. . . . The man who gives himself out as the inventor, is quite incapable of making such a ther- mometer as I wish to have : and I have vainly endeavoured to make him understand,” &c. — Sagredo to Galileo, March 15, GG- Chap. III. 1612. Sagredo’s letters on the thermome- ter or ther- moscope. Santorio.