I mounted it in a wooden
tube, placed it on a wooden stand, and used it for a time thus
mounted; but getting disgusted with the tremor and inconvenience
I had to put up with, I resolved to construct for it an iron
equatorial stand. I made my patterns, got them cast, turned and
fitted them myself, grinding all the working parts together with
emery and oil, and fitted a tangent-screw motion to drive the
instrument in right ascension. Now I found the instrument a
pleasure to use; and I determined to add to it divided circles,
and to accurately adjust it to the meridian. I made my circles
of well-seasoned mahogany, with slips of paper on their edges,
dividing them with my drawing instruments, and varnishing them to
keep out the wet. I shall never forget that sunny afternoon upon
which I computed the hour-angle for Jupiter, and set the
instrument so that by calculation Jupiter should pass through the
field of the instrument at 1h. 25m. 15s. With my watch in my
hand, and my eye to the eye-piece, I waited for the orb. When
his glorious face appeared, almost in a direct line for the
centre of the field, I could not contain my joy, but shouted out
as loudly as I could,--greatly to the astonishment of old George
Johnson, the miller, who happened to be in the field where I had
planted my stand!
"Now, though I had obtained what I wanted--a fairly good
instrument,--still I was not quite satisfied; as I had produced
it by a fortunate chance, and not by skill alone.
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