as to reduce his daily allowance from a quantity varying from fifty or sixty to one hundred and fifty grains, down to one varying from seven to twelve grains; that in the year 1822 an appendix was added to the "Confessions" which contained a tabular statement of his further progress toward an absolute abandonment of the drug, and indicating his gradual descent, day by day, for thirty-five days, when the reader is naturally led to suppose that the experiment was triumphantly closed by his entire disuse of opium. I had failed, however, to observe that a few pages preceding this detailed statement the writer had given a faint intimation that the experiment had been a more protracted one than was indicated by the table. I had also failed to notice the fact that no real progress had been made during the first four weeks of the attempt: the average quantity of laudanum daily consumed for the first week being one hundred and three drops; of the second, eighty-four drops; of the third, one hundred and forty-two drops; and of the fourth, one hundred and thirty-eight drops; and that in the fifth week the self-denial of more than three days had been rewarded with the indulgence of three hundred drops on the fourth. A careful comparison of this kind, showing that in an entire month the average of the first week had been but one hundred and three drops, while the average of the last had been one hundred and thirty-eight drops, and that in the fifth week a frantic effort to abstain wholly for three days had obliged him to use on the fourth more than double the quantity to which of late he had been accustomed, would have prevented the incautious conclusion, suggested by his table, that De Quincey made use of laudanum but on two occasions after the expiration of the fourth week.