72 The American Geologist. Au^-ust, 1H97 
the}' did not lead up to some conclusion which it was liis en- 
deavor to nuiintain. "Let us then" he states, "carefully record 
all facts which we discover, and look confidently forward for 
some useful result." 
It was not without some exhortation that the people of 
Maine were induced to continue the appropriations long enough 
to complete the cursory survey which Jackson planned to per- 
form. Among other inducements, there were lectures on geolo- 
gy given before the legislature, of which reports appeared 
in the Kenebec Journal for 18.38. In fact he appears to have 
experienced the usual tribulations meted out to a state ge- 
ologist. 
This state has been surveyed once since Jackson's time, 
but our knowledge of its geology is much less complete than 
is that of many thousand square miles of western wilderness. 
Jackson had scarcely brought to a finish the survey of 
Maine before he was engaged by a committee appointed b}' 
the legislature of Rhode Island to undertake a geological 
and agricultural examination of that state. Two thousand 
dollars were appropriated for the purpose of defraying the 
costs. The contract was made in April, 1839, and on May 
25th 1810, the manuscript of his report was tendered for pub- 
lication. One thousand copies of the report were issued, be- 
ing the lirst and last official account of the natural resources 
of the Island state. 
From an examination of the report it appears that Jack- 
son made long excursions out of Providence, visiting the 
principal towns and traversing the important rock groups so 
as to obtain general cross-sections of the area. The knowledge 
he thus gained of the geological distribution was fairly accu- 
rate. The Carboniferous rocks were separated from the crys- 
talline and igneous rocks on the west and several minor sub- 
divisions in these latter were introduced upon the map. It is 
only within recent years that geologists have recognized in the 
"primary" rocks of this report infolded patches of probably 
Carboniferous rocks. 
Everywhere, Dr. Jackson came in contact with the people 
as was his wont in the examination of Maine. His report is 
a digest of his journeys with the elaborated results of his anal- 
yses of the minerals and soils of the state. 
