406 
Steam Culture. 
These slightly variable items — the rost of labour and that of 
coals — exercise a mutually compensating influence on the aggregate 
of the day's expenses ; for, as a rule, wages are higher in the 
manufacturing districts where coal is cheaper. 
The cost of removals lies in a small compass, but will vary 
considerably in different localities, and at different seasons. In 
order to deal fairly by the steam cultivator we must assume that 
the size of the fields and the condition of the roads are well 
adapted to its introduction. 
The more questionable points are : — 1st, How much the culti- 
vator must earn in a season, above its working expenses, to pay 
interest, cost of repairs, and depreciation in value ;* and, 2ndlv, 
over how many working days this charge may be distributed. 
In both these respects, the case of a cultivator worked by a pro- 
prietor on his own farm only will differ from that where the im- 
plement is let out for hire, and in full work during the whole 
season. And yet, unless there be definite economical advantages 
or disadvantages in the one mode of management or the other, 
the charge per day must be identical. 
Another difhculty arises with respect to the actual available 
power of the engine when economically worked, the difference 
between nominal and real horse-power being ill defined, and 
on the increase. On these two elements, the expenses of re- 
pairs, &c., and the amount of force acquired, the cost of steam- 
power depends. When this is determined we have still to com- 
pare it with that of horse-power, a power of which the value and 
efficiency vary considerably at different seasons of the year. And 
since steam-power will be available as a substitute at those times 
in which horse-power is in especial request, the latter must be 
set above its average value for the purposes of our comparison. 
An Average Day's Work. 
First, in the case of Fowler s Cultivator. On strong land five 
acres of ploughing seems to be a good average day's work, allow- 
nomy of fuel be obtained ; but that, on the contrary, the consumption of fuel in 
raising a given quantity of water into steam is the same, whatever be the amount 
of pressure." This concUision is hardly self-evident. 
The object being to generate steam-power, and that power depending on its 
elastic force, and that force on the pressure to which it is subjected, it would seem 
that any process is economical which with the same heat creates a greater force by 
the agency of " increased pressure ;" the consumption of fuel may be identical, and 
yet a great economy may be effected. 
Be this as it may, Mr. Fowler's engine at Canterbury did not appear practi- 
cally to economise fuel by working at a higher pressure than his competitors. 
* The expression " wear and tear " hardly represents, in a definite manner, the 
two separate considerations of the annual outlay on repairs, and that depreciation 
•which is as much due to modern improvements as to the general weariuii out of 
the parts. 
