Dating brookfield insulators
The pots we now examined were entirely open at the top.
In them the different ingredients are placed, in the proportions named above, and the whole thoroughly mixed together by the use of hoes and shovels. The beautiful purple or amber color we frequently see in wine bottles and heavy glass, is made precisely as we have already named, with certain additional portions of coloring matter.
In the formation of these articles a peculiar clay is used.
It is imported from Germany, and comes to this country in blocks that are cubes of about ten inches. It is quite dry and hard, but has the usual greasy feel of all clays.
The formula consists of three parts of raw clay, three parts pot shells, and two parts burnt clay; all of which must be thoroughly mixed and stamped before the composition is formed into rolls for building the pots. In the large room in which we now were, there were nearly fifty finished pots in process of drying, while the molders were at work making still more.
It seemed to us that there was already a large supply, but when it is stated that there are two furnaces all the time in blast, and that each furnace has eight of these large pots, the supply will not be considered a very large one. They must be gradually made and before completed a month is gone. There are a number of pot ovens in each of the glass houses or furnace rooms.
He then makes another pile and goes through the same treadmilling, until he has been twelve times over the whole, when the clay is considered sufficiently worked to be passed on to the molders.