[22] William Burling of Long Island was the first to conceive an abhorrence of slavery. Early in his career he began to speak of the wickedness of the institution at the yearly meetings of the Quakers. He wrote several tracts to publish to the world his views on this great question. His first tract appeared in 1718. It was addressed to the elders of the Friends to direct their attention to "the inconsistency of compelling people and their posterity to serve them continually and arbitrarily, and without any proper recompense for their services." See Clarkson's "History of the Abolition of the African Slave Trade," Volume I, pp. 146-147. [23] After Burling came Ralph Sandiford, a merchant engaged in business in Philadelphia. This man attracted the attention of his friends because he declined the assistance offered him by persons sufficiently wealthy to establish him in life, merely because they had acquired their wealth by enslaving Negroes. He not only labored among his own people for the liberation of the slaves, but boldly appealed to others. He finally expressed his sentiments in a publication called the "Mystery of Inquiry," a brief treatise on the evil of the institution of slavery. The importance attached to this work is that Sandiford published it and circulated it at his own expense despite the fact that he had been threatened with prosecution by the judge. This pamphlet was written in correct and energetic style, abounding with facts, sentiments and quotations, which showed the virtue and talents of the author and made a forceful appeal in behalf of the blacks. See Clarkson's "History of the Abolition of the Slave Trade," Volume I, pp. 147-148.