During the next year, at the pressing invitation of Washington, he again crossed the ocean, to witness the peaceful prosperity of the country whose government he had helped to found by twofold service in war and in diplomacy. Adopted child of the Republic, he surrendered himself for six months to the sympathies of the people, the delights of friendship, and the companionship of Washington, whom he visited at Mount Vernon, and with whom he journeyed. Nor did his partiality for Boston fail at this time, as a contemporary record shows. “The reception I met with in Boston,” he wrote, “no words can describe; at least it is impossible to express what I have felt.”[79] But, far more than all, the Slavery of the African race interested his heart, and would not allow him to be silent. In official answers to addresses of welcome from Legislatures of Southern States, he declared his desire to see these Legislatures commence the work of Abolition.[80] This was in 1784, before Clarkson, then a youth at the University, was inspired to write his Essay against Slavery, which was the glorious beginning of his lifelong career, and before Wilberforce brought forward his memorable motion in the British Parliament for the abolition of the slave-trade. If these words were of little effect at that early day, they bear witness none the less to the exalted spirit of their author. In taking leave of Congress, as he was about to embark, he let drop other words, exhibiting the same spirit, wherein may be seen the mighty shadow of the Future. “May this immense temple of Freedom,” he said, “ever stand _a lesson to oppressors_, _an example to the oppressed_, a sanctuary for the rights of mankind! and may these happy United States attain that complete splendor and prosperity which will illustrate the blessings of their government, and for ages to come rejoice the departed souls of its founders!”[81] Such utterance by a French noble tells that the Revolution was approaching.