and this duty was first undertaken on the 5th of July, 1792.  It may be noted that the date on which the celebration of the tercentenary of the University was held happens to coincide with the centenary of the first visitation of the observatory.  The visitors on the first occasion were A. Murray, Matthew Young, George Hall, and John Barrett.  They record that they find the buildings, books and instruments in good condition; but the chief feature in this report, as well as in many which followed it, related to a circumstance to which we have not yet referred.

In the original equipment of the observatory, Ussher, with the natural ambition of a founder, desired to place in it a telescope of more magnificent proportions than could be found anywhere else.  The Board gave a spirited support to this enterprise, and negotiations were entered into with the most eminent instrument-maker of those days.  This was Jesse Ramsden (1735-1800), famous as the improver of the sextant, as the constructor of the great theodolite used by General Roy in the English Survey, and as the inventor of the dividing engine for graduating astronomical instruments.  Ramsden had built for Sir George Schuckburgh the largest and most perfect equatorial ever attempted.  He had constructed mural quadrants for Padua and Verona, which elicited the wonder of astronomers when Dr. Maskelyne declared he could detect no error in their graduation so large as two seconds and a half.  But Ramsden maintained that even better results would be obtained by superseding the entire quadrant by the circle.  He obtained the means of testing this prediction when he completed a superb circle for Palermo of five feet diameter.  Finding his anticipations were realised, he desired to apply the same principles on a still grander scale.  Ramsden was in this mood when he met with Dr. Ussher.  The enthusiasm of the astronomer and the instrument-maker communicated itself to the Board, and a tremendous circle, to be ten feet in diameter, was forthwith projected.

Projected, but never carried out.  After Ramsden had to some extent completed a 10-foot circle, he found such difficulties that he tried a 9-foot, and this again he discarded for an 8-foot, which was ultimately accomplished, though not entirely by himself.  Notwithstanding the contraction from the vast proportions originally designed, the completed instrument must still be regarded as a colossal piece of astronomical workmanship.  Even at this day I do not know that any other observatory can show a circle eight feet in diameter graduated all round.