PRACTICAL PAPERS—ARTIFICIAL STONE. 
373 
cribed were tried, Messrs. Donkin have set another pair of the artificial 
stones to work, and these, which are now in regular use, have given even 
more satisfaction than those first tried. The saving in time, and consequently 
in labor, effected by the use of the artificial grindstones, is, in fact, so great, 
that Messrs. Donkin have determined to use these stones exclusively in future; 
and we may add that the artificial stones are so much preferred by the work¬ 
men, that those men, even, who are employed in shops at some distance from 
that in which the stones at present in use are situated, prefer taking the 
trouble to go to them to using the Newcastle stones in their own shops. In 
addition to their great eflSciency the artificial grindstones possess the ad¬ 
vantages of being able to be manufactured of any size, and of any degree of 
coarseness of grain, and they can thus be specially adapted to any particular 
class of work, while the process of their manufacture insures their being of 
uniform texture throughout, and free from the flaws and hard and soft places 
found in natural stones. Altogether, we believe, that the general adoption 
of the artificial grindstones is merely a matter of time,” 
