Mag?iesia?i Series of tJte Northwestern States 123 



crystalline character of the shales associated with them, leads 

 to the conclusion that the dolomites and all associated rocks 

 must have undergone extensive chemical changes. 



5. The dolomites assume many interesting characters. The 

 development of rhombohedral grains is a very general process ; 

 the structure of the rhombohedra presents many crystallographic 

 features; locally too, the formation of a siliceous oolite is equally 

 characteristic of the Shakopee. 



December 6, 1892. 



IPaper H] 



METEOROLOGICAL STATISTICS 

 By William Cheney 



These statistics are the result of personal Meteorological 

 Observations, made at Minneapolis, Minnesota, by William 

 Cheney, voluntary observer United States Weather Bureau 

 since 1864. The tables here given cover the period from 

 1883 to 1894 inclusive and are followed by a Summary of mean 

 weather conditions and dates of maximum and minimum tem- 

 peratures. 



