On the other hand, there exists abundance of evidence that Smith was busy for most of three years after this date, and mainly in London, altering, improving, and adding to the manuscript of the book. New lines of investigation would suggest themselves, new theories to be thought out, and the task would grow day by day by a very simple but unforeseen process of natural accretion. Hume thought it near completion in 1769; but towards the end of 1772, a couple of months after Smith's answer to Pulteney, he gives it most of another year yet for being finished. He writes from his new quarters in St. Andrew Square, asking Smith to break off his studies for a few weeks' relaxation with him in Edinburgh about Christmas, and then to return and finish his work before the following autumn. ST. ANDREW'S SQUARE, _23rd November 1772_. DEAR SMITH--I should agree to your Reasoning if I could trust your Resolution. Come hither for some weeks about Christmas; dissipate yourself a little; return to Kirkaldy; finish your work before autumn; go to London, print it, return and settle in this town, which suits your studious, independent turn even better than London. Execute this plan faithfully, and I forgive you.... Ferguson has returned fat and fair and in good humour, notwithstanding his disappointment,[224] which I am glad of. He comes over next week to a house in this neighbourhood. Pray come over this winter and join us.--I am, my dear Smith, ever yours, DAVID HUME.[225]