The marvellous increase of national wealth in Great Britain since the reign of George III. is to be mainly ascribed to two mechanical agencies鈥攖he spinning-jenny and the steam-engine; both of which, however, would have failed to produce the results that have been attained if there had not been a boundless supply of cotton from the Southern States of America to feed our manufactories with the raw material. The production was estimated in bales, which in 1832 amounted to more than 1,000,000; and in 1839 was upwards of 2,000,000 bales. It appears from Mr. Woodbury's tables, that in 1834 sixty-eight per cent. of all the cotton produced in the world was shipped for England. In this case the demand, enormous as it was, produced an adequate supply. But this demand could not possibly have existed without the inventions of Hargreaves, Arkwright, Crompton, and Cartwright, in the improvement of spinning machinery.?