P. 153. _Denzil Street._--Here, about the middle of the street, on the south side, lived Theophilus Holdred, a jobbing watchmaker, whose name will always hold a place in one department of mathematical history. He discovered a method of approximating to the roots of numerical equations, of considerable ingenuity. He, however, lost in his day and generation the reputation that was really due to him for it, by his laying claim to more than he had effected, and seeking to deprive other and more gifted men of the reputation due to a more perfect solution of the same problem. He was, indeed, brought before the public as the tool of a faction; and, as the tools of faction generally are, he was sacrificed by his own supporters when he was no longer of any use to them. I once called upon him, in company with Professor Leyburn, of the Royal Military College, but I forget whether in 1829 or 1830. We found him at his bench--a plain, elderly, and heavy-looking personage. He seemed to have become "shy" of our class, and some time and some address were requisite to get him to speak with any freedom: but ultimately we placed him at his ease, and he spoke freely. We left him with the conviction that he was the _bonâ fide_ discoverer of his own method; and that he had no distinct conception, even then, of the principle of the methods which he had been led by his friends to claim, of having _also_ discovered _Horner's_ process before Horner himself had published it. He did not (ten years after the publication of Horner's method) even then understand it. He understood his own perfectly, and I have not the slightest doubt of the correctness of his own statement, of its having been discovered by him fifty years before. P. 166. _Dulwich Gallery._--This is amongst the unfortunate consequences of taking lists upon trust. Poor Tom Hurst[1] has not been in the churchyard these last eight years--except the three last in his grave. The last five years of his life were spent in a comfortable asylum, as "a poor brother of the Charterhouse." He was one of the victims of the "panic of 1825;" and though the spirit of speculation never left him, he always failed to recover his position. He is referred to here, however, to call Mr. Cunningham's attention to the necessity, in a _Hand-book_ especially, of referring his readers correctly to the places at which _tickets_ are to be obtained for any purpose whatever. It discourages the visitor to London when he is thus "sent upon a fool's errand;" and the Cockney himself is not in quite so good a humour with the author for being sent a few steps out of his way. P. 190. _Rogers_--a Cockney by inference. I {291} should like to see this more decidedly established. I am aware that it is distinctly so stated by Chambers and by Wilkinson; but a remark once made to me by Mrs. Glendinning (the wife of Glendinning, the printer, of Hatton Garden) still leads me to press the inquiry.