William Herschel, who was not deterred by the many engagements of his musical profession from devoting himself to the grinding of specula. But this is only one of many similar cases. The greatest imxprovement in the telescope, since the date of its invention, is due to a Spitalfields silk-weaver, John Dolland. His family were exiled from France by the revocation of the Edict of Nantes, and found a home in the suburbs of London. The devotion of the Spitalfields weavers to mathematics is one of the most curious as well as the most gratifying passages in the history of science; and John Dolland shone as one of the most distinguished of the number. He did not scruple to break a lance with the illustrious Euler; and for his improvements in the telescope, he received the highest honour of the Royal Society,—viz., the award of the Copley medal. He was the founder of the fortunes of his family, though it was his son Peter who amassed the wealth that flowed from the achromatic, arrangement. Peter, like his father, plied the shuttle in his youth, but he soon abandoned it for the more promising field of optics. Ramsden, who gained so much celebrity for his skill in dividing astronomical instruments, was a Yorkshire clothier. It would be easy to mention the names of many others, who, while they did not abandon the trade or profession in which they were trained, yet found time to improve the telescope, and advance the cause of astronomy. It is pleasant to record such
