Читать книгу The Writings of Thomas Jefferson, Vol. 6 (of 9) - Томас Джефферсон, Thomas Jefferson - Страница 14

Monticello, November 15, 1811.

Sir,—Your favor of October 14 was duly received, and with it Mr. Bowditch's observations on the comet, for which I pray you to accept my thanks, and be so good as to present them to Mr. Bowditch also. I am much pleased to find that we have so able a person engaged in observing the path of this great phenomenon; and hope that from his observations and those of others of our philosophical citizens, on its orbit, we shall have ascertained, on this side of the Atlantic, whether it be one of those which have heretofore visited us. On the other side of the water they have great advantages in their well-established observatories, the magnificent instruments provided for them, and the leisure and information of their scientific men. The acquirements of Mr. Bowditch in solitude and unaided by these advantages, do him great honor.

With respect to the eclipse of September 17. I know of no observations made in this State but my own, although I had no doubt that others had observed it. I used myself an equatorial telescope, and was aided by a friend who happened to be with me, and observed through an achromatic telescope of Dollard's. Two others attended the time-pieces. I had a perfect observation of the passage of the sun over the meridian, and the eclipse commencing but a few minutes after, left little room for error in our time. This little was corrected by the known rate of going of the clock. But we as good as lost the first appulse by a want of sufficiently early attention to be at our places, and composed. I have no confidence, therefore, by several seconds, in the time noted. The last oscillation of the two luminaries was better observed. Yet even there was a certain term of uncertainty as to the precise moment at which the indenture on the limb of the sun entirely vanished. It is therefore the forming of the annulus, and its breaking, which alone possess my entire and complete confidence. I am certain there was not an error of an instant of time in the observation of either of them. Their result therefore should not be suffered to be affected by either of the others. The four observations were as follows:

I have thus given you, Sir, my observations, with a candid statement of their imperfections. If they can be of any use to Mr. Bowditch, it will be more than was in view when they were made; and should I hear of any other observations made in this State, I shall not fail to procure and send him a copy of them. Be so good as to present me affectionately to your much-esteemed father, and to accept the tender of my respect.