After all, I long to be in America again, nay, if I can go home to return no more to Europe, it seems to me that I shall ever enjoy more peace of mind, & even Physical comfort than I can meet with in any portion of the world beside.[118] While at Charleston in the previous winter, Audubon had worked diligently at his letterpress, and no doubt, before returning to Europe had his "biographical" materials well in hand. We have seen that at Edinburgh in the autumn of 1830 he entered upon a businesslike arrangement with William MacGillivray to assist him with the technical portions of the _Ornithological Biography_. The part which his young assistant played in this work was long a subject of dispute, until letters of both which showed the precise character of the relations between them were finally published. Immediately upon his return to England Audubon again applied to his young friend, and received from him the following letter:[119] _William MacGillivray to Audubon_ EDINBURGH, 11 GILMORE PLACE. _28th May 1834._ DEAR SIR, I am glad to hear of your safe arrival, which I did not expect so soon, and pleased to find you in good health and high spirits. As you have the kindness to inquire respecting myself and family, I am happy to inform you that we are all very well, contented and busy. My head and hands are quite full—abundance of work and sufficient pay—time to ramble now and then for the purpose of hammering rocks, pulling plants, and shooting birds. You say you have accumulated a mass of materials which you are desirous of seeing in print, and propose that I should revise it as before. I shall be glad to do so, if you please, and willing that you confer the benefit on another, if you find it expedient. As to the terms, let them be such as you please with respect to money; but as time is valuable to me, I should like that arrangements be made so as to prevent unnecessary loss of it, by letting me have manuscripts, books, &c. in due array. The skins of which you speak I apprehend cannot be disposed of here to any great extent; but I believe shells might be sold to advantage, and bring higher prices than in London.