The association's official minutes for 24 July record that he had misinformed it about the German law students' attitude towards an impending election.

Of such usurpers I might name not a few, but I shall pass them over now in silence, as it is customary for first offences to receive less severe punishment than subsequent ones. But I shall not remain silent any longer about a second offender who has tried too audaciously to do to me the very same thing which he did many years ago by appropriating the invention of my geometric compass, despite the fact that I had many years previously shown it and discussed it before a large number of gentlemen and had finally made it public in print. May I be pardoned if, against my nature, my habit, and my present intentions - I show resentment and cry out, perhaps with too much bitterness, about a thing which I have kept to myself these many years. I speak of Simon Mayr of Gunzenhausen; he it was in Padua, where I resided at the time, who set forth in Latin the use of the said compass of mine and, appropriating it to himself, had one of his pupils print this under his name. Forthwith, perhaps to escape punishment, he departed immediately for his native land, leaving his pupil in the lurch as the saying goes; and against the latter, in the absence of Simon Mayr, I was obliged to proceed in the manner which is set forth in the Defence which I then wrote and published. Four years after the publication of my 'Sidereal Messenger', this same fellow, desiring as usual to ornament himself with the labours of others, did not blush to make himself the author of the things I had discovered and printed in that work. Publishing under the title of 'The Jovian World', he had the temerity to claim that he had observed these Medicean planets which revolve about Jupiter before I had done so. But because it rarely happens that truth allows herself to be suppressed by falsehood, you may see how he himself, through his carelessness and lack of understanding, gives me in that very work of his the means of convicting him by irrefutable testimony and revealing unmistakably his error, showing not only that he did not observe the said stars before me but even that he did not certainly see them until two years afterwards; and I say moreover that it may be affirmed very probably that he never observed them at all.
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Next, notice the craft with which he tries to show himself prior to me. I wrote in my 'Sidereal Messenger' of making my first observation on the seventh of January, 1610, continuing then with others on the succeeding nights. Along comes Mayr, and, appropriating my very observations, he prints in the title page of his book and again in the opening part of his work that he had already made his observations in the year 1609, trying to give people the idea that he was first. The earliest observation that he produces as made by him is the second one made by me; yet he announces it as made in the year 1609. What he neglects to mention to the reader that since he is outside our church and has not accepted the Gregorian calendar, the seventh day of January of 1610 for us Catholics, is the same as the twenty-eighth day of December of 1609 for those heretics. So much for the priority of his pretended observations.