1782, to write down and describe all remarkable appearances I
saw in my 'sweeps.' But it was not till the last two months of
the same year that I felt the least encouragement to spend the
starlit nights on a grass-plot covered with dew or hoar-frost,
without a human being near enough to be within call. I knew
too little of the real heavens to be able to point out every
object so as to find it again without losing too much time
by consulting the Atlas. But all these troubles were removed
when I knew my brother to be at no great distance, making
observations with his various instruments on double stars,
planets, and the like; and I could have his assistance
immediately when I found a nebula, or cluster of stars, of
which I intended to give a catalogue. I had the comfort to
see," she continues, "that my brother was satisfied with my
endeavours to assist him when he wanted another person either
to run to the clocks, write down a memorandum, fetch and carry
instruments, or measure the ground with poles,--of which
something of the kind every moment would occur."

The conscientious care and assiduous industry with which Herschel made
his measurements of the diameter of the Georgium Sidus (now called
Uranus), and his interesting observations of other planets, of double
stars with their coloured light, of cometary and nebulous appearances,
were truly remarkable; as may be seen by the various papers which
he wrote at this time for the Royal Society. In addition to all this
labour, he perfected a twelve-inch speculum of vast magnifying power
before the spring of 1784; and many hours were spent at the
turning-bench, as not a night clear enough for observing ever passed
without the devising of improvements in the mounting and motion of
the various instruments then in use, or the test and trial of