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Royal Academy, and has an English micrometer; having a moveable wheel, and divided into minutes; and by means of a screw to the index of the quadrant, together with the division of the nonnius plate fastened to it, was so applied, that during the whole time of the observation, while the wire of the plummet constantly glided upon the same point of the limb, it might be moved in the limb by a vertical motion in either direction by the alidad alone. This most excellent invention of your’s I first brought into Germany, to the best of my knowlege, after I had seen it’s power at Paris in the hands of the ingenious M. Le Monier.
Besides the quadrant, Dollond’s telescope, and several other astronomical tubes of 6, 8, 13, and 22 feet; we had a Newtonian telescope of 4 feet Austrian measure, with an eye glass of 13 of an inch.
We had a clock made by M. le Paute, a Parisian, very well defended from the rays of the Sun and from the wind, which I accommodated to this business for a month before, in many celestial observations with as much accuracy as I could, and with more success than we could well expect.
| The interior contact of the western limb of Venus, with the western limb of the Sun, observed with Dollond's telescope—— |  |
True time. | ||
| h | , | ,, | ||
| 20 | 53 | 8 | ||
| The moment of the egress, wherein the same limb of the Sun after the interior contact first appeared corniculated, most accurately observed with the same telescope, was—— | |
20 | 53 | 35 |
| Whence I conclude, that the interior contact happened—— |  |
20 | 53 | 3312 |
