702 : GEOLOGY OF OHIO. 
are pared and broken but not sorted over.. They are washed before 
shipping, so that they are much finer than in nature. The Blue Ridge 
is the finer-grained of the two. The Mineral Point calcined clay is not 
now largely used, because the extensive connection of the company allow 
them to get back their old potshells for calcine, which, being already in 
the desired composition of the mixture, make a better calcine than any 
single clay. 
These shells are chipped with small hammers until no part of the 
surface remains and only the clean interior is left. The charge is com- 
posed quite largely of calcine with a little flint clay, and the remainder 
German and Missouri bond-clays. The mixture is ground in a dry pan 
and sifted by a jig bolt, and the coarse part re-ground. It: is then 
pugged five or six times in succession and then is stored and blanketed. 
It remains in this state until it sours and smells offensively, which the 
men claim is necessary to its proper working. Itis wedged by hand and 
isready for use. ‘The pots are large structures about 5 feet high, 4 feet 
wide and 4 feet long, bounded on top and sides by covered walls, 
and on the bottom by a flat face. They weigh from 2,000 to 3,000 
pounds, and sometimes as much as 3,500 pounds. They are made from 
3 to 5 inches thick with a thicker floor, and are each built on a small 
platform covered with gravel, so that air may circulate beneath them 
and dry them faster. They are built entirely by hand, small pieces 
being added daily, and left to harden before another addition is made. 
Each builder, of which there are four, has on hand 12 or 15 pots at once, 
on which he daily builds a little more, until at the end of three weeks or 
a month he finishes them all together. Thus about 60 pots a month 
is found to be the average turnout of the works. The building is a 
large four-story, provided with elevators so that the heavy pots can be 
handled without danger of hurting them. They are dried from one to 
six months, and the longer the better, and are shipped on three-wheeled 
trucks, which are returned to the works, so that they are loaded and 
unloaded with ease and security, where before there was always great 
danger of breaking them. Each pot is worth from $60 to $75. The 
quality of the ware made at these works is excellent, and has a wide cir- 
culation amongst glass workers. The works are under most intelligent 
supervision, and the process would furnish material for a much fuller 
description if space allowed. 
