Page:Sir William Herschel, his life and works (1881).djvu/99

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of William Herschel.
77

£2,000 would be granted for enabling him to make himself an instrument.

"Immediately every preparation for beginning the great work commenced. A very ingenious smith (Campion), who was seeking employment, was secured by my brother, and a temporary forge erected in an upstairs room."

The sale of these telescopes of Herschel's must have produced a large sum, for he had made before 1795 more than two hundred seven-feet, one hundred and fifty ten-feet, and eighty twenty-feet mirrors. For many of the telescopes sent abroad no stands were constructed. The mirrors and eye-pieces alone were furnished, and a drawing of the stand sent with them by which the mirrors could be mounted.

In 1785 the cost of a seven-foot telescope, six and four-tenths inches aperture, stand, eye-pieces, etc., complete, was two hundred guineas, a ten-foot was six hundred guineas, and a twenty-foot about 2,500 to 3,000 guineas. He had made four ten-foot telescopes like this for the king. In 1787 Schroeter got the mirrors and eye-pieces only for a four-