1878. Machines are agents for abridging manual labour. All the operations of gardening might be performed by the simple tools, instruments, or utensils already mentioned; but, in practice, some labours would be insufferably tedious, and others inconveniently cumbersome; and, in many operations, the ordinary force of man could not be conveniently brought into action. Rollers, as opposed to the turf-beetle, are illustrative of the first case; the German devil, and Bramah's hydrostatic press, as opposed to a number of men with ropes or levers, of the second; and the boat-scythe, as performing the operations of the pincers or common scythe, of the third case. But the machines of gardening are very few, and consist chiefly of artificial contrivances for the defence of gardens, or of scientific machines for measurement or designation of temperature. In contriving either of these, simplicity ought to be attended to; for a complicated machine is not only more expensive, and more apt to be out of order, but there is also a greater degree of friction, according to the number of nibbing parts,
