For many years this number was invariably adopted, and many of the present generation will remember how they were taught in their school-days that the sun was 95,000,000 miles away. At length doubts began to be whispered as to the accuracy of this result. The doubts arose in different quarters, and were presented with different degrees of importance; but they all pointed in one direction, they all indicated that the distance of the sun was not really so great as the result which Encke had obtained. It must be remembered that there are several ways of finding the distance of the sun, and it will be our duty to allude to some other methods later on. It has been ascertained that the result obtained by Encke from the observations made in 1761 and 1769, with instruments inferior to our modern ones, was too great, and that the distance of the sun may probably be now stated at 92,000,000 miles. I venture to record our personal experience of the last transit of Venus, which we had the good fortune to view from Dunsink Observatory on the afternoon of the 6th of December, 1882. The morning of the eventful day appeared to be about as unfavourable for a grand astronomical spectacle as could well be imagined. Snow, a couple of inches thick, covered the ground, and more was falling, with but little intermission, all the forenoon. It seemed almost hopeless that a view of the phenomenon could be obtained from that observatory; but it is well in such cases to bear in mind the injunction given to the observers on a celebrated eclipse expedition. They were instructed, no matter what the day should be like, that they were to make all their preparations precisely as they would have done were the sun shining with undimmed splendour. By this advice no doubt many observers have profited; and we acted upon it with very considerable success. There were at that time at the observatory two equatorials, one of them an old, but tolerably good, instrument, of about six inches aperture; the other the great South equatorial, of twelve inches aperture, already referred to. At eleven o'clock the day looked worse than ever; but we at once proceeded to make all ready. I stationed Mr. Rambaut at the small equatorial, while I myself took charge of the South instrument. The snow was still falling when the domes were opened; but, according to our prearranged scheme, the telescopes were directed, not indeed upon the sun, but to the place where we knew the sun was, and the clockwork was set in motion which carried round the telescopes, still constantly pointing towards the invisible sun. The predicted time of the transit had not yet arrived.