282 
[Assembly 
and the magnetic oxide. In fact there are but few sections of coun 
try so full of ore, as East-Moriah, some account of which, has been 
given in the annual reports. The hypersthene rock is the most impor- 
tant and extensive formation in the county. It commences at the dis- 
tance from the lake just mentioned, and continues nearly to the extreme 
western border. It is an unstratified rock, but breaks into angular 
blocks or tables, whose general form is rhombic. This cleavage, as it 
may be termed, might be mistaken in some cases, for stratification ; but 
the whole system of fissures, resembles those planes which result from 
crystallization, and not those of deposition. 
As it regards the western limit of the hypersthene rock, I would re- 
mark again that it extends only 4 or 5 miles west of the village of Mc- 
Intyre. We have at its western termination, a recurrence of gneiss ac- 
companied with its usual associates, the coarse, white, primary, lime 
rock, narrow veins of the magnetic oxide, and probably of the serpentine 
and soapstone. It is an important consideration, that limestone makes 
its appearance so near the establishment. It may in fact, be consider- 
ed as sufficiently near the works ; for it is better that all those opera- 
tions which consume the fuel, should be distributed widely over the 
country, than concentrated at one point. The hauling of the lime a 
few miles, is a matter of less consequence, than the entire consumption 
of fuel, in the immediate vicinity of a great establishment, when opera- 
tions are entirely dependent on wood. The limestone in many places, 
is impure. It contains imbedded minerals, as pyroxene, quartz, phos- 
phate of lime, mica, hornblende, &c. The softer strata in the vicinity 
of the iron works, are peat, felsphatic clays and gravels. The marshy 
grounds, are sometimes shaky and wet, yet as they are invariably fur- 
nished with hard bottoms at no great depth, there is no obstacle to the 
construction of the best of roads over them. In concluding this outline 
of the geology of Essex, it is sufficient to observe, that I have mention- 
ed the most important rocks which are found in the county. The par- 
ticular localities at which they occur, is not an important subject for our 
'present consideration ; their general arrangement may be learned by 
the sectional line, which has been described, Avhen passing from Cedar- 
Point to the western border of the county, through Moriah and New- 
comb, along the travelled road. The erratic blocks which are scattered 
over the surface, are the hypersthene masses, and small boulders of 
sandstone. The former, are by far the most abundant. The latter, 
have a northern origin, and have evidently been transported by agents, 
