By some curious growth of sentiment, which cannot be accurately traced, _Classification_ rather than _Separation_, became the leading idea of those interested in prison reform. Howard was quoted as the authority for Classification, but it must be remembered that Howard was chiefly moved by the physical suffering of prisoners, and, with him, classification did not mean much more than to separate the debtor from the felon, the guilty from the innocent, the men from the women, and the adult from the child,--and this by a system of separate confinement described in the Act of 1778. The classification in the sense in which it affected the movement of opinion in the first quarter of the last century went further than this. It seems to have assumed that if prisoners in the same categories, and, therefore, presumably of more or less the same moral characters, were associated together in common rooms or dormitories, no evil results were likely to follow, and facilities for labour, according to Bentham's ideas, would be greatly improved; and thus we find that in 1823, the Act of 4 Geo. IV., c. 64, in so far as discipline is concerned, gave effect mainly to this principle. Many extensive and important prisons were erected in conformity with this Act, notably at Maidstone, Derby, Westminster, Chelmsford, and Leicester, in which the Governor's house was usually placed in the centre with detached blocks of cells radiating from it. The average size of the cells was only about eight feet by five feet, with a day room and yard of proportionate size for each different class or category of prisoners. The only inspection was from the central building, and there was no interference with the unrestricted association of prisoners, and the greatest neglect, disorder, or irregularities might go on unperceived; and it soon became manifest that, to whatever extent classification might be carried, there was no moral standard by which it could be regulated, nor any limit short of individual separation that could secure any single prisoner from contamination. The mischievous effect of this Act was soon condemned by public opinion, and two Parliamentary inquiries were held in 1832 and 1836, which concurred in the strong opinion that more efficient regulation should be established in order to save all prisoners, especially the untried, from the frightful contamination resulting from unrestricted intercourse. It was at this time that the great controversy between the so-called "Silent" and "Separate" Systems sprang up in the United States, and its echo was felt throughout the civilized world. The rival systems of Auburn and of Philadelphia became the historic battleground in which was fought out the great and burning controversy which centred round the question of the proper treatment of prisoners, and established the importance of the now accepted principle that prison discipline shall be reformatory at least to this extent,