504 Scientific Intelligence. 
The holes in which we placed slow registering Negretti and 
Zambra thermometers were drilled, slightly inclined upward, to a 
depth of ten feet from the face of the rock and plugged with wood 
and clay. In these holes the thermometers were lett from one to 
three months. The average annual temperature of the air is 48° 
F., the temperature of the air in the bottom of the shaft was 72° 
K. | Aine, As 
2. Geological Atlas of the United States.—The first number 
of this great work of the United States Geological Survey has 
been completed and issued in twelve separate folios. Each folio 
contains, on sheets of heavy paper, 183 by 214 inches in size, two 
or more pages of description, four maps, and sometimes a fifth, 
illustrating the topography, the areal geology, the economic 
geology and the structural geology of the particular area sur- 
veyed ; a fifth map-sheet, containing column sections, is added in 
several of the folios. On the inside of the stiff manilla covers is 
printed explanations of the topographic map, the geologic map 
and their uses. The scale of the mapsin this atlas is mainly of the 
medium size adopted, viz. z55'55,73; the sheets of the Livingston 
folio are of the smaller scale, sz>45y7, and those of Anthracite- 
Crested Butte folio are of the gz}, scale. The Cripple Creek 
special map (in folio 7) is on the still larger scale of sztoz. 
Contour intervals of 200 feet are expressed on the maps of the 
smaller scale, of 100 feet in the medium and larger scale, and of 
50 feet in the special Cripple Creek map. 
The geological features of the regions are expressed on the 
maps by colors and various patterns of* dots and circles, and 
tints, overprinted or underprinted, and letter symbols, the mean- 
ing and use of which are clearly defined in the general explana- 
tion on the covers and in the special legend of each map. The 
maps are models of artistic beauty and perfection, and were 
engraved and printed by the U. 8. Geological Survey, Bailey 
Willis editor, and 8. J. Kiibel chief engraver. 
In the first number of the Atlas are the following twelve folios : 
1. Livingston folio, Montana, by Iddings and Weed geologists, 
Arnold Hague in charge. 
2. Ringold folio, Georgia-Tennessee, by C. W. Hayes. 
3. Placerville folio, Cal., by Lindgren and Turner, Becker in 
charge. 
. Kingston folio, Tenn., by C. W. Hayes. 
. Sacramento, Cal., by Lindgren, Becker in charge. 
. Chattanooga, Tenn., by C. W. Hayes. 
. Pike’s Peak, Col., by Whitman Cross. 
With a special sheet, the Cripple Creek special map also 
by Mr. Cross. 
. Sewanee, Tenn., by C. W. Hayes. 
. Anthracite-Crested Butte, Col., by Cross and Eldridge, Em- 
mons in charge. 
10. Harpers Ferry, Va., Md., W. Va., by Arthur Keith. 
11. Jackson, Cal., by H. W. Turner, Becker in charge. 
at G> Or fm 
© 
