Issue was once more joined both in England and America on the constitutional power of taxation. The great principle of English law that taxation was not a right, but a gift of the persons taxed through their representatives, was claimed also by the colonies. Opinions had repeatedly been given by the law officers of the Crown that a colony could be taxed only by its own representatives. The actual amount of money called for was too small to burden them, but it was to be applied in such a way as to make the governors and judges independent of the assemblies. The principle of taxation, once admitted, might be carried farther. As an English official of the time remarked: "The Stamp Act attacked colonial ideas by sap; the Townshend scheme was attacking them by storm every day." 28. COLONIAL PROTESTS AND REPEAL (1767-1770). [Sidenote: Colonial protest.] [Sidenote: Massachusetts circular.] [Sidenote: Coercive measures.] This time the colonies avoided the error of disorderly or riotous opposition. The leading men resolved to act together through protests by the colonial legislatures and through non-importation agreements. Public feeling ran high. In Pennsylvania John Dickinson in his "Letters of a Farmer" pointed out that "English history affords examples of resistance by force." Another non-importation scheme was suggested by Virginia, but was on the whole unsuccessful. In February, 1768, Massachusetts sent out a circular letter to the other colonies, inviting concerted protests, and declaring that the new laws were unconstitutional. The protest was moderate, its purpose legal; but the ministry attempted to destroy its effect by three new repressive measures. The first of them, April, 1768, directed the governors, upon any attempt to pass protesting resolutions, to prorogue their assemblies. The second was the despatch of troops to Boston: they arrived at the end of September, and remained until the outbreak of the Revolution. The third coercive step was a proposition to send American agitators to England for trial, under an obsolete statute of Henry the Eighth. [Sidenote: Effect of the tax.] Meanwhile the duties had been levied. The result was the actual payment of about sixteen thousand pounds; this sum was offset by expenses of collection amounting to more than fifteen thousand pounds, and extraordinary military expenditures of one hundred and seventy thousand pounds. Once more the ministry found no financial advantage and great practical difficulties in the way of colonial taxation. Once more they determined to withdraw from an untenable position, and once more, under the active influence of the king and his "friends," they resolved to maintain the principle. In April, 1770, all the duties were repealed except that upon tea. Either the ministry should have applied the principle rigorously, so as to raise an adequate revenue, or they should have given up the revenue and the principle together.