[...] The Irish were, a Catholic priest admitted in 1836, ‘more prone to take part in trades unions, combinations and secret societies than the English’. ‘They are the talkers and ring-leaders on all occasions,’ claimed another witness. Engels saw the ‘passionate, mercurial Irish temperament’ as the precipitate which brought the more disciplined and reserved English workers to the point of political action:

… the mixing of the more facile, excitable, fiery Irish temperament with the stable, reasoning, persevering English must, in the long run, be productive only of good for both. The rough egotism of the English bourgeoisie would have kept its hold on the working-class much more firmly if the Irish nature, generous to a fault, and ruled primarily by sentiment, had not intervened, and softened the cold, rational English character in part by a mixture of the races, and in part by the ordinary contact of life.

We may dispute Engels’ language of ‘nature’ and ‘race’. But we need only replace these terms to find that his judgement is valid. It was an advantage to the employers, at a time when precision engineering coexisted with tunnelling by means of shovel and pick, to be able to call upon both types of labour. But the price which had to be paid was the confluence of sophisticated political Radicalism with a more primitive and excitable revolutionism. [...]