318 
The Trials of Ploughs at Warwich. 
of fun’ow, and laid and bi’oke tlie furrow to perfection ; but at 
the greater depths of eight and ten inches it lost points con- 
siderably, and therefore was not regarded by the Judges as a 
generally useful plough. 
The tables given on pages 314 to 316 suinmai’ise the work 
done in the various classes in the field trials. For these and 
the foregoing details we are indebted to Mr. W. Newton. 
Dynamometer Trials. 
Before proceeding to an examination of the tabulated results 
of these trials, a few preliminary notes as to the manner in 
which they were conducted, and how the figures were andved 
at, may not only be of interest, but may further lead to a better 
appreciation of the results obtained, more particularly when it 
comes to making any kind of comparison between them and the 
tabulated results given of the last trials of horse jiloughs made 
by the Society at Hull. 
AVhen it was decided to carry out the present trials, one of 
the first questions raised was whether the then existing plough 
dynamometer, which was used at Hull and at previous trials, 
was all that could be desired. Experience gained in its use, 
on several occasions, pointed out modifications in details which 
might advantageously be made with the view of facilitating its 
manipulation, and also of improving the registration of work 
done. In order that the records of these trials might be made 
as reliable as possible, the Society ordered a new dynamometer 
to be made, and it afibrds the writer (who had also used the 
older instrument) considerable satisfaction to be able to report 
the very uniform working and recording of the same in the 
present trials. 
As in many tests of ploughs the draught is approximately 
measured by introducing between the horses and the iJough a 
spring link or balance (which is not infrequently dignified by 
the name of a dynamometer), and the oscillations of the pointer, 
varying with every step of the hoi-ses as well as Avith the resist- 
ance offered, are merely estimated by the eye and noted, a 
general description of the instrument used may not be out of 
place. 
A Avrought-iron frame is mounted on three Avheels AA'ith 
standards adjustable, both vertically and horizontally, tAA'O small 
Avheels on one side running in the furroAV and one larger wheel 
on the land side. The boss of this larger AA’heel is geared so as 
to lake a pitch chain, which chain actuates by means of a worm 
and AA crm-Avheel a brass drum, causing it to revolve, the ratio 
