Eighteen months might be carried out in a Cell, 13 feet long by 7 broad by 7 feet high. Under six months, the discipline might in my opinion be safely enforced in the Cell 11 feet by 6 - but where separation by night only is required, the prisoners working in association during Public Works - the Cells are only 7 feet long by 4 broad and 7 feet high, divided by partitions of corrugated Iron.
I should consider these latter sleeping Cells too small and would recommend that Cells for such a purpose should be 9 feet long by 5 broad, each having a window.
In all cases perfect ventilation as possible should be obtained - either artificially or by natural means of a free egress for foul air, and a corresponding means of ingress for fresh air, without subjecting the occupier to a draft. All this however, subject to any local peculiarities of climate.
Page 239