208 
I Assembly 
ance of evidence, that matter, though inert in itself, obeys the impulse 
of an invisible intangible power, v^rhich, though slovf in its operations, 
yet, in the end produces many remarkable results, 
Without occupying farther time in the exposition of the manner in 
which the porcelain clay is formed originally, or of the changes which 
subsequently takes place in them, I have only to remark in this con- 
nection, that the occurrence of those masses of hornstone and chalce- 
donic quartz, in place, furnishes us the means of solving a geological 
fact of some importance, as the following statement will show. Over 
a wide extent of country, embracing a portion of the States of New- 
York, Vermont and Massachusetts, there occurs small boulders of this 
peculiar hornstone and chalcedony. They are found loose upon the sur- 
face and in the soil, intermixed with other rocks as granitic gneiss and 
hornblende; but so far as I have observed, they are never found im- 
bedded in a rock; hence their original formation, and their actual repo- 
sitories were matters of doubt and uncertainty. We have, however, 
reason to infer that they were originally formed in beds of clay, simi- 
lar to those of Johnsburgh and Athol, and that currents of water, or 
some other forces, have transported them from their native beds, and 
spread them over a wide extent of country. 
Before closing my remarks on the porcelain clay of Warren county, 
I think it possible some of the readers of the geological reports may be 
interested in the general description of this valuable substance as it occurs 
in foreign localities, and of those varieties which are employed in the 
manufacture of this beautiful ware. The Kaolin, or porcelain earth, is 
derived from the same source, wherever it has occurred. It may always 
be traced to the coarse granite as its parent rock, and particularly to the 
disintegration and decomposition of the feldspar. All the ordinary 
feldspars possess the property of forming an enamel before the blow- 
pipe, without addition, previous to the change of state which reduces 
them to the condition of an earth. 
But subsequently to this change in consequence of parting with the 
potash, one of the elements of this mineral, it no longer possesses the 
property of forming an enamel by fusion; or in other words, it becomes 
infusible, and remains unchanged when exposed to the highest heat of 
a furnace. In this remark the petuntze of the Chinese is an exception. 
In this, the decomposition has not proceeded so far as to effect an entire 
alteration in its elements, and it still retams the property of the origi- 
nal feldspar, that of fusing and forming an enamel when subjected to a 
