Page:Sir William Herschel, his life and works (1881).djvu/97

Rh well as myself. To make observations with such large machinery, where all around is in darkness, is not unattended with danger, especially when personal safety is the last thing with which the mind is occupied; even poor Author:Giuseppe Piazzi did not go home without getting broken shins by falling over the rack-bar.

"In the long days of the summer months many ten and seven foot mirrors were finished; there was nothing but grinding and polishing to be seen. For ten-foot, several had been cast with ribbed backs, by way of experiment, to reduce the weight in large mirrors. In my leisure hours I ground seven-foot and plain mirrors from rough to fining down, and was indulged with polishing and the last finishing of a very beautiful mirror for Sir.

"An account of the discoveries made with the twenty-foot and the improvements of the mechanical parts of the instrument during the winter of 1785 is given with the catalogue of the first 1,000 new nebulæ. By which account it must plainly appear that the expenses of these improvements, and those which were yet to be made in the apparatus of the twenty-foot (which, in fact, proved to be a model of a larger instrument), could not be supplied out of a salary of £200 a year, especially as my brother's finances had been too much reduced during the six months before he received his first quarterly payment of fifty pounds (which was Michaelmas, 1782). Travelling from Bath to London, Greenwich, Windsor, backwards and forwards, transporting the telescope, etc.,