He succeeded tolerably well.
He taught himself geometry and mathematics, and daily application made him more perfect in his studies.

In course of time an extraordinary ambition took possession of him: no less than the construction of a reflecting telescope of six inches diameter.

The idea would not let him rest until he had accomplished his purpose.

He cast and polished the speculum with great labour; but just as he was about to finish it, the casting broke! What was to be done?
About one-fifth had broken away, but still there remained a large piece, which he proceeded to grind down to a proper diameter.

His perseverance was rewarded by the possession of a 3 1/2 inch speculum, which by his rare skill he worked into a reflecting telescope of very good quality.
He was, however, so much annoyed by the treacherously brittle nature of the speculum metal that he abandoned its use, and betook himself to glass.