Note 9 — LETTER LXVII.
Reading edition
10. The use of machinery9 in agriculture throws a certain number of persons out of wholesome employment, who must thenceforward either do nothing, or mischief. The use of machinery in art destroys the national intellect; and, finally, renders all luxury impossible. All machinery needful in ordinary life to supplement human or animal labour may be moved by wind or water: while steam, or any modes of heat-power, may only be employed justifiably under extreme or special conditions of need; as for speed on main lines of communication, and for raising water from great depths, or other such work beyond human strength.