The Trials of Grist Mills and Disintegrators at Plymouth. 617 
made for the sake of adjustment, were taken no note of, and, 
lurino- the trial proper, each machine received a measured dose, 
first of bones, and afterwards of cotton-cake. The time occu- 
pied in disintegration was noted by chronograph, while the 
power absorbed was registered continuously by the recording 
dynamometer, samples of the products being taken from time to 
time, as the work went on, for subsequent examination and 
i iid <r iu°'. 
if The Hardy Pick Co.'s "Devil" disintegrator (No. 2539), 
which ultimately received the First Prize, was the first machine 
Hardy Patent Pick Co.'s First Prize "Devil" Disintegrator. 
tried. It consists of a pair of grinding rings, one fixed and 
the other revolving, whose contiguous surfaces are furnished 
with teeth arranged in concentric circles, and diminishing in 
size towards the peripheries of the grinding rings, but so dis- 
posed that each ring of teeth travels between similar rings of 
teeth on the opposing annulus, as shown in the accompanying 
woodcut. . w j 
VOL. I. T. s.— 3 S 8 
