172 Bibliographical Notices. 
The agricultural geology of the State (pp. 42, &c.) has received 
considerable attention from Dr. Gwen and his assistants ; and the 
soils have been extensively analysed. Dr. R. Peter’s report on the 
chemical analysis of soils, subsoils, under-clays, clays, and nitre- 
earths, with some general observations on soils, occupies pp. 163- 
294, 
The thermal waters of Hot-Spring county are fully treated of at 
pp. 18, &c., and at pp. 101, &c. Silica and carbonate of lime are 
their most abundant mineral constituents. Their temperature ranges 
from 100° to 148° Fahr. ' They issue, with much free carbonic acid, 
mostly from a snowy-white chalcedonic novaculite (the ‘ Ouachita 
oilstone,”’ or ‘Arkansas whetstone’), in upwards of torty springs, on 
a ridge (Whetstone Mountain) about 250 feet above the valley, and 
deposit much calcareous tufa. ‘The novaculite varies in character, is 
much fissured and veined with quartz. In Montgomery county, 
some twenty miles distant, the sandstones are less altered, but have 
their joints and planes of stratification filled with fine clusters of 
crystals of silex, as much as 5 or 6 inches in length, and of unsur- 
passed purity. The valley below the springs is occupied with silicified 
slate, traversed by veins of serpentine. No igneous rock is exposed 
nearer than ten miles off, at Viga Creek, on the borders of Magnet 
Cove, famous for its magnetic iron-ore and great variety of minerals, 
including titanic acid (Brookite or Arkansite), . 
. Artesian wells are treated of in chap. 3, including those of Louis- 
ville and St. Louis,—the former 2086 feet, the latter 2199 feet deep. 
Mention also is made of several of the best-known in Europe. 
. This Report is illustrated with a chart of the principal hot springs 
in Hot-Spring county, with several plates and woodcuts illustrating 
the topographical features, and with the engraved plates of fossils 
already noticed above. M. Leo Lesquereux’s Report on the Botany 
and Paleontology of the State (pp. 295-399) comprises a systematic 
catalogue of the plants of Arkansas, with useful notes appended. 
There is also a good index to the whole book. 
This useful work must have been very welcome to the inhabitants 
of Arkansas, and is full of interest to geologists abroad and at home. 
Its getting-up does credit to the State, whose late Governor, his 
Excellency E. N. Conway, appears to have warmly and judiciously 
patronized the Survey. The geological results of the reconnaissance 
are worthy of the veteran geologist and his assistants; and it is fer- 
vently hoped that the detailed survey of the State will be strenuous] 
proceeded with under equally good auspices as soon as peace shall 
have again calmed existing disturbances in the distracted States of 
North America. 
