[_A MONOTONOUS WALK._] Horror at the crime, at the stain of innocent blood which now defiled his country, seems to have swallowed up all expression of personal feeling. By degrees the rigour of his imprisonment appears to have been a little relaxed, and by the connivance of his gaoler he obtained the opportunity, rarely granted to prisoners, of walking upon the leads of one of the towers. Thither he daily went for his exercise, and, says the writer of the 'Parentalia,' 'by a just computation, he walked round the world. The earth being affirmed to be 216,000 miles in compass (at a calculation of sixty miles to a degree);[54] if it were possible to make a path round the earth, an able footman going constantly twenty-four miles a day, would compass it in 900 days, and so on in proportion of time and miles.' It would seem that the Bishop, finding his life was for the time spared, and having a steady conviction that the evil days would pass, had determined to keep himself ready in body, as in soul, for what work the future might bring. A prison life leaves little to be recorded; the days wore away in the Tower, divided between devotion, study, and that unchanging monotonous walk which at least gave the prisoner a distant glimpse of the world from which he was excluded. He was allowed the Bible and paper and ink, but no other books. It is the testimony of one who has studied Bishop Wren's manuscript-- 'He wrote in an exquisite hand, in very fair Latin, a commentary on much of Holy Scripture enough to fill an oak box of no mean dimensions. This box he committed to the care of Dr. Beaumont, master of S. Peter's College.[55] Had the Puritans read the MS. they would have found some antidote to their poison.' Two sermons and some treatises were also written during his captivity. Probably suspicion attached to anything that he did, for it is said to have been all written by stealth. His nephew's life differed as widely from his own as did their characters. Christopher was at Oxford, deep in the experiments of the 'New learning,' and in the inventions which it suggested to his ready brain and dexterous fingers. [_DIPLOGRAPHIC PEN._] One invention which he was at the time proud of was that of a-- 'diplographic instrument for writing with two pens,' whose uses he thus describes; 'by the help of this instrument, every ordinary penman may at all times be suddenly fitted to write two several copies of any deeds and evidences, from the shortest to the longest length of lines, in the very same compass of time, and with as much ease and beauty, without any dividing or ruling; as, without the help of the instrument, he could have despatched but one.'