There was nothing, however, to which the jealous sensibilities of the colonies were more alive than to any attempt of the mother country to draw a revenue from them by taxation. From the earliest period of their existence, they had maintained the principle that they could only be taxed by a Legislature in which they were represented. Sir Robert Walpole, when at the head of the British government, was aware of their jealous sensibility on this point, and cautious of provoking it. When American taxation was suggested, "it must be a bolder man than himself," he replied, "and one less friendly to commerce, who should venture on such an expedient. For his part, he would encourage the trade of the colonies to the utmost; one half of the profits would be sure to come into the royal exchequer through the increased demand for British manufactures. _This_" said he, sagaciously, "_is taxing them more agreeably to their own constitution and laws_." Subsequent ministers adopted a widely different policy. During the progress of the French war, various projects were discussed in England with regard to the colonies, which were to be carried into effect on the return of peace. The open avowal of some of these plans, and vague rumors of others, more than ever irritated the jealous feelings of the colonists, and put the dragon spirit of New England on the alert. In 1760, there was an attempt in Boston to collect duties on foreign sugar and molasses imported into the colonies. Writs of assistance were applied for by the custom-house officers, authorizing them to break open ships, stores, and private dwellings, in quest of articles that had paid no duty; and to call the assistance of others in the discharge of their odious task. The merchants opposed the execution of the writ on constitutional grounds. The question was argued in court, where James Otis spoke so eloquently in vindication of American rights, that all his hearers went away ready to take arms against writs of assistance. "Then and there," says John Adams, who was present, "was the first scene of opposition to the arbitrary claims of Great Britain. Then and there American Independence was born." Another ministerial measure was to instruct the provincial governors to commission judges. Not as theretofore "during good behavior," but "during the king's pleasure." New York was the first to resent this blow at the independence of the judiciary. The lawyers appealed to the public through the press against an act which subjected the halls of justice to the prerogative. Their appeals were felt beyond the bounds of the province, and awakened a general spirit of resistance.