Laudator Temporis Acti

Boswell: The Ominous Years, 1774-1776, edd. Charles Ryskamp and Frederick A. Pottle (New York: McGraw-Hill Book Company, Inc., 1963), pp. 124-125 (April 6, 1775):

I maintained a strange proposition to Burke: that it was better for a Scotsman and an Irishman to preserve so much of their native accent and not to be quite perfect in English, because it was unnatural. I would have all the birds of the air to retain somewhat of their own notes: a blackbird to sing like a blackbird, and a thrush like a thrush, and not a blackbird and other birds to sing all like some other bird. Burke agreed with me. Englishmen would laugh heartily, and say, "Here an Irishman and a Scotsman, each with his own country tone strong, attempt to prove that it is better to have it." I said it was unnatural to hear a Scotsman speaking perfect English. He appeared a machine. I instanced Wedderburn. "A man of wood," said I, "or a man of brass." "Ay, a man of brass," cried Burke. Lord Lisburne and I had afterwards a dispute on this subject. My metaphor of the birds he opposed by saying, "A Scotsman may do very well with his own tone in Coll; but if he comes into the House of Commons, it will be better if he speaks English. A bagpipe may do very well in the Highlands, but I would not introduce it into Bach's concert." "This," said I, "shows what it is to argue in metaphors. One is just as good as another." But I maintained to my Lord that it put me in a passion to hear a Scotsman speaking in a perfect English tone. It was a false voice. He speaks as if he had some pipe or speaking instrument in his mouth. And I thought always, "Can't he take this confounded pipe out, and let us hear him speak with his own organs?" I do still think I am right.

For more on the subject see Pat Rogers, "Boswell and the Scotticism," in George Clingham, ed., New Light on Boswell (Cambridge: Cambridge University Press, 1991), pp. 56-71.