at the Canterbury Meeting, ISliO. 
495 
Having thus obtained tlie cost of plougliing per acre by the diflcrcnt 
apparatus tested, we were desirous of comparing it with the cost of ploughing 
by tlio ordinary horse-labour of the farm ; and here we were enabled, by means 
of the very ingenious dynamometer of Mr. Amos and tlie valuable tabulated 
calculations of Mr. Morton,* to deal with more reliable data tlian mere opinions 
or estimates. To test the actual resistance of the soil, an ordinary iron plough 
(Busby's) was used, to which the dynamometer was attached, the traction 
force being supplied by the nearest engine. Six furrows were drawn in different 
parts of the field of the same depth and width as those turned by the steam- 
ploughs, the dynamometer giving the following results: — Average" distance 
travelled, 192 yards ; power consumed, 52 ; revolutions of counter, 21 ; time 
consumed, 3'7o min. ; and showing that the force required to overcome the 
resistance of the soil was 692'32 lbs., or rather more than the traction-power 
of 4 horses, moving at the rate of 2J miles per hour.f 
According to Mr. Morton, the average cost of horse-power on a farm may 
be taken at 6fZ. jier cwt., drawn 2i miles. In ploughing an acre of land, with 
a 10-inch furrow, the plough would have to J)e drawn about 10 miles : conse- 
quently, the draught, say G cwt. x by the distance 4, X by the cost per cwt., 
(M., would give 12s. per acre as the minimum cost of ploughing an acre of the 
land in question by horse-labour, which, indeed, was the estimate given by 
l)ractical farmers on the ground during the trials. 
The comparison, then, between steam and horse plouffhinrj is largely in favour 
of the former on ijrottnd offerin;/ such resistance. The least efficient of the 
competing machines (Beards') showed a saving of Is. lOd, per acre, = 15 per 
cent. Robey and Co.'s and Eddington's showed a saving of 5s. 4c?. per acre, 
or = 45 per cent. ; while Fowler's \\-ork was done at a saving of no less than 
7s. Gd. per acre, or C8 per cent, less than by horse-labour. 
The second set of trials took place on the following day (?th), in an 
adjoining field, where the increased inclination of the surface offered far greater 
obstacles to tillage cultivation. Indeed, the land had most probably never 
before been ploughed up and down, but always across the hill, and then evi- 
dently only in a very superficial manner. Directions were given for the 
several competitors to light up their fires, and to move, as soon as ready, to 
the stations allotted to them, and then to plough the area assigned to each. 
The length of the piece to be ploughed was 330 yards, the land having a rise 
of - 1 in 10 throughout the entire length, which, in one place, for a short dis- 
tance, was increased to 1 in 4J, as is shown at A and B in the accompanying 
section. Fowler's engine-fire was lighted at 9"12, and steam sufficient to 
move it to the new station was generated at lO'lS, when the necessary pre- 
parations for ploughing were made, and work commenced at 11 a.m. 
Bobey and Co. lighted up their fire at about the same time, and reached 
their station at 10'20. The necessary preparations were completed at 11'25, 
when they commenced work. 
The other two competitors, Beards and ]']ddingtou, withdrew from the trial 
after having commenced operations. Beards' ajiparatus, though quite suitable 
* " On the Cost of Horse-power," by J. C. Morton, R. A. S. Journal, vol. xix., 
p. 437. 
t Formula for reducing the results of plough dynamometer (Amos) : — 
2546 = constant number. 
2546 X N 
L 
2546 X N 
T X 11,000 
HP. 
S. 
N 
T 
L 
S 
HP 
No. of revolutions of counter, 
time in minutes, 
distance in yards, 
strain in lbs. ou ropes, 
horse-power. 
11,000 = A 
33,000 
3 ft. = 1 yard 
