464 



SCIENCE 



[N. S. VOL. XXXIII. No. 847 



cene. Unconformities occur between the Fort 

 Union and White Elver and between the White 

 Kiver and Loup Fork, while folds and faults 

 occur locally in the Pre-Loup Fork beds of Short 

 Pme Hills, etc. There are few fossil plants and 

 animals. Coal (lignite) of lower Fort Union age 

 occurs in seams a few inches to ten feet thick. 



The buttes are attributed to either (1) a chert 

 layer of the White River, (2) a massive Fort 

 Union sandstone, (3) local thick coarse beds of 

 Loup Fork, (4) combinations of the above. 



Soil has been extensively removed and eaves 

 worn in the cliffs by the work of wind. At Slim 

 Buttes and Short Pine Hills extensive slumping 

 has developed. Some terraces in the Little Mis- 

 souri Valley may be due to the post-Pliocene 

 climatic changes. 



Northern Canada (address of the retiring vice- 

 president) : E. W. Bbock. Eead by title only. 



Geology of the Olympic Feninsiila, Washington: 



A. B. Eeagan. 



In the Olympic Peninsula the following forma- 

 tions are exposed (1) Old Cretaceous (Point of 

 Arches group) ; (2) Cretaceous and possibly older 

 (Point Granville, Pacific coast in general, and 

 central high area) ; (3) Eocene (Volcanies near 

 Port Crescent) ; (4) Oligoeene-Miocene (Fresh 

 Water Bay and east of Gettysburg flank of the 

 Point of Arches Group); (5) Pliocene (Hoko 

 formation on the Strait, Eaft and Quinault forma- 

 tions toward Point Granville, and Quillayute for- 

 mation in the interior to the northeast of La Push 

 on the Pacific), and (6) Pleistocene (covering all 

 the region but the upper stretches of the eastern 

 tributaries of the Quillayute Eiver). In aU be- 

 tween 20,000 and 30,000 feet of rocks are exposed. 



The rocks of (4) contain many fossils very 

 similar to the Tertiary near Astoria, Ore. They 

 are also coal-bearing, the Clallam Bay Mine pro- 

 ducing 200 tons or more per month. Coal is also 

 exposed in the Quillayute-Bogachiel country and 

 on the Pacific coast near Cape Johnson, and also 

 near the Point of Arches. Oil springs occur at 

 Hoh Head, on the Pacific side of the peninsula. 



The Geologic Map of North DaJcota: A. G. 



Leonaed. 



The geologic formations represented on the map 

 are the Benton, Niobrara, Pierre, Fox HiUs, 

 Lance (Ueratops beds')?. Fort Union and White 

 Eiver. The Benton and Niobrara occur in the 

 northeastern corner of the state, in the Pembina 

 Mountains. The black to bluish gray Pierre shale 



covers most of the eastern half outside the Eed 

 Eiver Valley, and also outcrops in the Missouri 

 Eiver Valley for twenty miles above the South 

 Dakota line, and in a small area in northwestern 

 Bowman County. The Fox Hills sandstone occurs 

 in the latter locality and on the Missouri Eiver as 

 far north as old Fort Eice. The Lance beds cover 

 a large area in south-central North Dakota, and a 

 smaller area ia the southwestern corner of the 

 state. The Fort Union occupies much of the 

 western half of the state, and in it most of the 

 lignite beds are formed. The White Eiver beds 

 form several small areas in Billings County. 



The character of the various formations is dis- 

 cussed. 



A Neiv Use of Lignite: E. J. Babcock. 



Eead by title only. 

 Coals and Clays of North Dakota: E. J. Babcock. 



Eead by title only. 

 Geologic Features of Nebraska: E. H. Barbour. 



Eead by title only. 



Lake Superior as a Former Igneous Center: 

 EOBERT Bell. 

 Eead by title only. 

 The General Structure of the Florence Iron Dis- 

 trict: W. O. HOTCHKISS. 



The Florence Iron District is the extension into 

 Wisconsin of the Menomiaee district of Michigan. 

 The Quinnesee schists south of both districts have 

 been considered to be the basement on which the 

 iron-bearing series was deposited and therefore 

 the possibility of developing new iron districts to 

 the south deemed very slight. Work of the past 

 neld season has shown that these schists overlie 

 the iron-bearing series. The general structure of 

 the Florence district is monoclinal from a broad 

 point of view, with local folding in the slate series 

 in which the iron formations are interbedded. 



The iron-bearing series has a southward dip and 

 disappears under the schists. This makes it more 

 probable that the series may leappeat beneath the 

 glacial drift to the southward and makes careful 

 work in the drift covered pre-cambrian area to 

 the south of great economic importance. 



The Geothermal Gradient: Alexandee N. 



WiNCHELL. 



It is generally agreed that the earth is a cooling 

 body. Calculations of the thermal gradient within 

 the earth, based on the laws of a cooling body, 

 have shown that the gradient thus derived does 

 not deviate from a straight line to any important 

 amount within a depth of fifteen or twenty miles. 



