With increasing evidence of the Negro's capacity for mental improvement, and fitness for the duties and blessings of a freeman, and the growing insolence and rigorous policy of the mother country, came a wonderful change in the colony. The Negroes were emboldened to ask for and claim rights as British subjects, and the more humane element among the whites saw in a relaxation of the severe treatment of the blacks security and immunity in war. But anti-slavery sentiment in Massachusetts was not born of a genuine desire to put down a wicked and cruel traffic in human beings. Two things operated in favor of humane treatment of the slaves,--an impending war, and the decision of Lord Mansfield in the Sommersett case. The English government was yearly increasing the burdens of the colonists. The country was young, its resources little known. The people were largely engaged in agricultural pursuits. There were no tariff laws encouraging or protecting the labor or skill of the people. Civil war seemed inevitable. Thoughtful men began to consider the question as to which party the Negroes of the colony would contribute their strength. It was no idle question to determine whether the Negroes were Tories or Whigs. As early as 1750 the questions as to the legality of holding Negroes in slavery in British colonies began to be discussed in England and New England. "What, precisely, the English law might be on the subject of slavery, still remained a subject of doubt."[358] Lord Holt held that slavery was a condition unknown to English law,--that the being in England was evidence of freedom. This embarrassed New-England planters in taking their slaves to England. The planters banded for their common cause, and secured the written opinion of Yorke and Talbot, attorney and solicitor general of England. They held that slaves _could_ be held in England as well as in America; that baptism did not confer freedom: and the opinion stood as sound law for nearly a half-century.[359] The men in England who lived on the money wrung from the slave-trade, the members of the Royal African Company, came to the rescue of the institution of slavery. In order to maintain it by law in the American colonies, it had to be recognized in England. The people of Massachusetts took a lively interest in the question. In 1761, at a meeting "in the old court-house," James Otis,[360] in a speech against the "writs of assistance," struck a popular chord on the questions of "The Rights of the Colonies," afterwards published (1764) by order of the Legislature. He took the broad ground, "that the colonists, black and white, born here, are free-born British subjects and entitled to all the essential rights of such."[361] In 1766 Nathaniel Appleton and James Swan distinguished themselves in their defence of the doctrines of "liberty for all." It became the general topic of discussion in private and public, and country lyceums and college societies took it up as a subject of