which I wished to
undertake, the President of the Royal Society, who is always ready
to promote useful undertakings, had the goodness to lay my design
before the king. His Majesty was graciously pleased to approve of
it, and with his usual liberality to support it with his royal
bounty.

"In consequence of this arrangement I began to construct the
forty-foot telescope about the latter end of 1785.[33] The woodwork
of the stand and machines for giving the required motions to the
instrument were immediately put in hand. In the whole of the
apparatus none but common workmen were employed, for I made drawings
of every part of it, by which it was easy to execute the work, as I
constantly inspected and directed every person's labor; though
sometimes there were not less than forty different workmen employed
at the same time. While the stand of the telescope was preparing, I
also began the construction of the great mirror, of which I
inspected the casting, grinding, and polishing, and the work was in
this manner carried on with no other interruption than that
occasioned by the removal of all the apparatus and materials from
where I then lived, to my present situation at Slough.

"Here, soon after my arrival, I began to lay the foundation upon
which by degrees the whole structure was raised as it now stands,
and the speculum being highly polished and put into the tube, I had
the first view through it on February 19, 1787. I do not, however,
date the completing of the instrument till much later. For the first
speculum, by a mismanagement of the person who cast it, came out
thinner on the centre of the back than was intended, and on account
of its weakness would not permit a good figure to be given to it.

"A second mirror was cast January 26, 1788, but it cracked in
cooling. February 16 we recast it, and it proved to be of a proper
degree of strength. October 24 it was brought to a pretty good
figure and polish, and I observed the planet _Saturn_ with it. But
not being satisfied, I continued to work upon it till August 27,
1789, when it was tried upon the fixed stars, and I found it to give
a pretty sharp image. Large stars were a little affected with
scattered light, owing to many remaining scratches on the mirror.
August the 28th, 1789, having brought the telescope to the parallel