I have duly received your favor of June the 6th, and immediately communicated its contents to a member of the Academy. He told me that they had received the other copy of your memorial, which you mention to have sent through another channel; that your ideas were not conveyed so explicitly, as to enable them to decide finally on their merit, but that they had made an entry in their journals, to preserve to you the claim of the original idea. As far as we can conjecture it here, we imagine you make a table of variations of the needle, for all the different meridians whatever. To apply this table to use in the voyage between America and Europe, suppose the variation to increase a degree in every one hundred and sixty miles. Two difficulties occur; 1. a ready and accurate method of finding the variation of the place; 2. an instrument so perfect, as that (though the degree on it shall represent one hundred and sixty miles) it shall give the parts of the degree so minutely, as to answer the purpose of the navigator. The variation of the needle at Paris, actually, is 21° west. I make no question you have provided against the doubts entertained here, and I shall be happy that our country may have the honor of furnishing the old world, what it has so long sought in vain. I am with much respect, Sir, your most obedient, humble servant, Th: Jefferson. LETTER LXXXIII.--TO MONSIEUR L HOMMANDE, August 9, 1787 TO MONSIEUR L HOMMANDE. Paris, August 9, 1787. Sir, At the time you honored me with your letter of May the 31st, I was not returned from a journey I had taken into Italy. This circumstance, with the mass of business which had accumulated during my absence, must apologize for the delay of my answer. Every discovery, which multiplies the subsistence of man, must be a matter of joy to every friend to humanity. As such, I learn with great satisfaction, that you have found the means of preserving flour more perfectly than has been done hitherto. But I am not authorized to avail my country of it, by making any offer for its communication. Their policy is to leave their citizens free, neither restraining nor aiding them in their pursuits. Though the interposition of government in matters of invention has its use, yet it is in practice so inseparable from abuse, that they think it better not to meddle with it. We are only to hope, therefore, that those governments, who are in the habit of directing all the actions of their subjects by particular law, may be so far sensible of the duty they are under of cultivating useful discoveries, as to reward you amply for yours, which is among the most interesting to humanity. I have the honor to be, with great consideration and respect, Sir, your most obedient and most humble servant, Th: Jefferson. LETTER LXXXIV.--TO PETER CARR, August 10, 1787 TO PETER CARR. Paris, August 10, 1787. Dear Peter,