The "condition of England," as it was then loosely termed, was the first subject which claimed the attention of Liverpool's government. While Perceval was congratulating parliament on the elasticity of the revenue, a widespread depression of industry was producing formidable disturbances in the midland counties. This depression was the consequence partly of the continental system, crippling the export of British goods to European countries; partly of the revival, in February, 1811, of the American non-intercourse act, closing the vast market of the United States; and partly of the improvements in machinery, especially those in spinning and weaving machines introduced by the inventions of Cartwright and Arkwright. Unhappily, this last cause, being the only one visible to artisans, was regarded by them as the sole cause of their distress. During the autumn and winter of 1811 "Luddite" riots broke out among the stocking-weavers of Nottingham. Their name was derived from a half-witted man who had destroyed two stocking frames many years before. Frame-breaking on a grand scale became the object of an organised conspiracy, which extended its operations from Nottinghamshire into Derbyshire, Leicestershire, Lancashire, and Yorkshire. At first frame-breaking was carried on by large bodies of operatives in broad daylight, and when these open proceedings were put down by military force, they were succeeded by nightly outrages, sometimes attended by murder. Early in 1812 a bill was passed making frame-breaking a capital offence. In spite of this riots grew into local insurrections, and a message from the prince regent on June 27 recommended further action to parliament. It was natural, in that generation to connect all disorderly movements with revolutionary designs, and this belief underlies an alarmist report from a secret committee of the house of lords on the prevailing tumults. Accordingly, Sidmouth obtained new powers for magistrates to search for arms, to disperse tumultuous assemblies, and to exercise jurisdiction beyond their own districts. In November many Luddites were convicted, and sixteen were executed by sentence of a special commission sitting at York. These stern measures were effectual for a time, and popular discontent in the manufacturing districts ceased to assume so acute a form until after the war was ended.