. . . "In my brother's absence from home I was, of course, left alone to amuse myself with my own thoughts, which were anything but cheerful. I found I was to be trained for an assistant astronomer, and, by way of encouragement, a telescope adapted for 'sweeping,' consisting of a tube with two glasses, such as are commonly used in a 'finder,' was given me. I was 'to sweep for comets,' and I see, by my journal, that I began August 22d, 1782, to write down and describe all remarkable appearances I saw in my 'sweeps,' which were horizontal. But it was not till the last two months of the same year that I felt the least encouragement to spend the star-light 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 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, etc., and when I could have his assistance immediately if I found a nebula or cluster of stars, of which I intended to give a catalogue; but, at the end of 1783, I had only marked fourteen, when my sweeping was interrupted by being employed to write down my brother's observations with the large twenty-foot. I had, however, the comfort to see that my brother was satisfied with my endeavors 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, etc., etc., of which something of the kind every moment would occur. For the assiduity with which the measurements on the diameter of the _Georgium Sidus_, and observations of other planets, double stars, etc., etc., were made, was incredible, as may be seen by the various papers that were given to the Royal Society in 1783, which papers were written in the daytime, or when cloudy nights interfered. Besides this, the twelve-inch speculum was perfected before the spring, and many hours were spent at the turning-bench, as not a night clear enough for observing ever passed but that some improvements were planned for perfecting the mounting and motions of the various instruments then in use, or some trials were made of new constructed eye-pieces, which were mostly executed by my brother's own hands. Wishing to save his time, he began to have some work of that kind done by a watchmaker who had retired from business and lived on Datchet Common; but the work was so bad, and the charges so unreasonable, that he could not be employed. It was not till some time afterwards, in his frequent visits to the meetings of the Royal Society (made in moonlight nights), that he had an opportunity of looking about for mathematical workmen, opticians, and founders. But the work seldom answered expectation, and it was kept, to be executed with improvements by ALEXANDER during the few months he spent with us.