28) Review of Dr. Jackson’s Final Report 
the first of the following June, 1840. By the terms of his en- 
gagement he was expected to complete the survey in three years ; 
and it was understvod of each year, four months should be devoted 
to field operations and four to the analysis of minerals. ‘This 
would of course leave four months for the less active, though not 
less important duties appertaining to the survey—in reviewing 
the proceedings in the field, and in preparing maps, with such 
other documents as might be necessary in a final report—a suf- 
ficiently short time for the purpose. So extensive and laborious, 
however, were the operations of the laboratory, that these alone, 
we are informed, instead of taking only four months of the year, 
required nearly all the eight not allotted to the field ; a fact which, 
in view of what was accomplished in this way, will hardly sur- 
prise any one at all aware of the time necessary for the accurate 
analysis of minerals. Notwithstanding this, Dr. Jackson seems 
by no means to have limited himself to the specified duties of 
his commission, arduous as they were; on the contrary, he has 
contributed largely of his observations upon the agriculture 
of the State, and has furnished numerous analyses of the soils, 
neither of which were required of him by the authority under 
which he acted. 
In the introduction, so called, to the work, after some observa- 
tions upon the utility of such surveys as the one authorized by 
the State, our author proceeds to give a general view of the va- 
rious rock formations that compose the strata of the earth’s crust 
and of the fossils that characterize a portion of them. In remark- 
ing upon the Silurian and Cambrian rocks of Murchison and 
Prof. Sedgwick, (the New York system of the New York geol- 
ogists, ) he takes occasion to object, and most justly, to the course 
adopted by some of introducing local names to define classes of 
rocks found in every quarter of the earth. It is much to be hoped 
that his views in this particular may generally prevail; whilst at 
the same time, it may be remarked that a numerical arrangement, 
for which he expresses a preference, might not be found wholly 
free from objection. 
In the brief but comprehensive view given of the various 
formations of the earth’s surface, those which are developed in 
the strata of New Hampshire have of course received particular 
attention. In this connection, we are informed that a great anti~ 
clinal axis of primary rocks exists in New Hampshire, the trans- 
