284 
[Assembly 
by oil of vitriol. These serpentines are at least new varieties for our 
country. Some have a peculiar appearance, like bronze, owing to small 
gold-like particles, with a lamillar structure, resembling bronzite or dial- 
lage metalloide. Also, other particles highly translucent, like precious 
serpentine, with frequently small nuclei resembling devitrifications or 
porcelanites, coloured white, yellow, blood red, variegated, &c. The 
grain of this kind is like common serpentine. In other kinds, the mass 
seems to be made of small globuliform concretions, varying in size, be- 
ing centres of aggregation; some are of dark vitrious and serpentine, 
others of the compact kind, the enveloping part of a light colour. The 
first impression of this rock is like some of the New- Jersey trap-rocks, 
where amphibole is in imperfect crystals, or like a pyroxenic lava, with 
its imperfect crystals imbedded in the more compact material. 
These two principal varieties produce endless mixtures upon the 
small scale, to say nothing of those derived from difference of shades 
of colour, the presence of veins and mixtures with the associated shales. 
These serpentines seem to resemble the ophiolites of Tuscany and 
Florence, and should the views of Brocchi be correct, they may not only 
be similar in origin but in age. The objections which Mr. Brongniart 
makes to the very modern characters which their associates present, are 
all in perfect accordance with those of the New-York rocks, and no one 
acquainted with the facts which the survey has made known, at all doubts 
that those rocks belong to the period, or age, intermediate to the crys- 
talline or primary rocks, and the coal of Pennsylvania; in other words, 
to the transition class. 
Of the specimens collected during the survey of 1838, there are six- 
teen boxes in the rooms of the Third and Fourth Districts, at the State 
House. 
I had intended to have given a list of the fossils which have been 
found in each rock and group, but circumstances render it proper to de- 
fer the same to the next report. 
Since concluding my report I have again had the pleasure of hearing 
from Judge Allen, giving the progress made in boring since the 28th 
December. At that period the depth was 531 feet, and in red shale. 
Since then the boring has attained to the depth of 550 feet, being an 
advance of 19 feet. Within the depth of 536 feet it was thought that 
about one foot of light coloured sandstone, very hard, had been drilled, 
and followed at 536 feet by what was called blue limestone. The Judge 
writes, " It probably is that. It is very hard; we bore only about 18 
