This is the basis of the power of concerted action among workers.

But the measure of this power depends in the main upon two considerations.
First comes the degree of effectiveness in combination.

The prime requisites for effective combination are a spirit of comradeship and mutual trust, knowledge and self-restraint in the disposition of united force.

Education and free and frequent intercourse can alone establish these elements of effective combination.

And here the first difficulty for workers in "sweating" trades appears.