The existence of slavery in the American colonies had attracted criticism from both sides of the Atlantic as many could not reconcile the existence of the institution with the eglitarian ideals espoused by leaders of the Revolution. British writer Samuel Johnson wrote that "how is it we hear the loudest yelps for liberty among the drivers of the Negroes?" in a text opposing the greivances of the colonists. Referring to this contradiction, English abolitionist Thomas Day wrote in a 1776 letter that "if there be an object truly ridiculous in nature, it is an American patriot, signing resolutions of independency with the one hand, and with the other brandishing a whip over his affrighted slaves".(2) At: Internet Archive : The Johns Hopkins University Sheridan Libraries : James Birney Collection of Antislavery Pamphlets .</ref> African-American writer Lemuel Haynes expressed similar viewpoints in his essay "Liberty Further Extended" where he wrote that "Liberty is Equally as preious to a Black man, as it is to a white one". Thomas Jefferson unsuccessfully attempted to include a section in the Declaration of Independence which asserted that King George III had "forced" the slave trade onto the colonies. Despite the turmoil of the period, African-Americans contributed to the foundation of an American national identity during the Revolution. Phyllis Wheatley, an African-American poet, popularized the image of Columbia to represent America. She came to public attention when her "Poems on Various Subjects, Religious and Moral" appeared in 1773, and received praise from George Washington.