Report on the Trials of Implements at Oxford. 511 
on shelves, and the clay brought from the pug mill for from 2s. ZJ. to 2s. OfZ.a 
thousand, and wc much qnestion if the woi'k can be done cheaper and as well 
by any power machine. It is quite a different question with bricks. The 
weight of clay is so much greater that it must be slow work by hand, and 
machinery answers well because it is not necessary to have such accuracy. In 
Pinfold's largest machine— a splendid affair— the cutting apparatus is driven by 
gearing Ironi the machine, and cuts as the clay is travelling, so no stop is neces- 
sary. ^The cut is a little straggling owing to the resistance of the clay and the 
Fig. 15— iHr. J. D. Pinfold's Tile-maJcing Machine, No. 6674. 
spring of the wire, but it is not at all the worse, but rather an advantage, as the 
mortar takes a better hold ; but with pipes a clean cut is most important, other- 
wise continuity cannot be maintained. Pinfold's machines are so made that they 
can deal with clay in a moderately dry state, and for brickmaking it is not 
necessary (though it is generally desirable) to prepare clay in any way. The 
large machine has a patent self-acting feed, consisting of powerful screws which, 
as "they work the clay forward, subject it to the action of a pug mill._ The 
rollers are provided with a safety brake, so that if any stone or tool got in, the 
machine is brought to a standstill. The rollers are powerful, and great care is 
taken to lubricate the clay and prevent undue friction by a proper supply of water. 
The self-acting cutter, which is very ingenious, consists of a large wheel with 
