But Boulton was more than a man of business, continues Smiles; he was a man of culture, and the friend of educated men. His hospitable mansion at Soho was the resort of persons eminent in art, in literature, and in science; and the love and admiration with which he inspired such men affords one of the best proofs of his own elevation of character. Among the most intimate of his friends and associates were Richard Lovell Edgeworth, a gentleman of fortune, enthusiastically devoted to his long-conceived design of moving land-carriages by steam; Captain Keir, an excellent practical chemist, a wit and a man of learning; Dr. Small, the accomplished physician, chemist and mechanist; Josiah Wedgwood, the practical philosopher and manufacturer, founder of a new and important branch of skilled industry; Thomas Day, the ingenious author of "Sandford and Merton"; Dr. Darwin, the poet-physician; Dr. Withering, the botanist; besides others who afterward joined the Soho circle, not the least distinguished of whom were Joseph Priestley and James Watt. The first business in hand was the reconstruction of the engine brought from Kinneil, which upon trial performed much better than before, wholly on account of the better workmanship attainable at Soho; but there still recurs the unceasing complaint that runs throughout the long eight years of trial--lack of accurate tools and skilled workmen, the difference in accuracy between the blacksmith standard and that of the mathematical-instrument maker. Watt and Boulton alike agreed that the inventions were scientifically correct and needed only proper construction. In our day it is not easy to see the apparently insuperable difficulty of making anything to scale and perfectly accurate, but we forget what the world of Watt was and how far we have advanced since.