﻿CONTENTS. 



Page 



Art. IX. — On hitherto unrecognized Wave-lengths ; by 



S. P. Langley " 83 



X. — On the chemical composition of Herderite and Beryl, 

 with note on the precipitation of aluminum and separa- 

 tion of beryllium and aluminum; by S. L. Penfield 

 and D. N. Harper. 107 



XI. — Communications from the IT. S. Geological Survey, 

 Division of the Rocky Mountains. VIII. On Ptilolite, 

 a new Mineral; by W. Cross and L. G. Ear ins 117 



XII. — Notes on the Peridotite of Elliot County, Kentucky; 



by J. S. Diller . ... 121 



XIII. — Temperature Observations at the Lake Superior 



Copper Mines; by H. A. Wheeler 126 



XIV. — An A] (plication of the Copper Reduction Test to the 

 Quantitative Determination of Arsenic; by II. Car* 

 michaei .- 129 



XV.— On the Crystallization of Gold; by E. S. Dana. . .. 



XVI. — Classification of the Cambrian System of North 



America; by C. D. Walcott ._. 138 



XVII.— Note on the Spectrum of Comet C. by O. T. 



Sherman _ 15 7 



EENTIFIC INTELLIGENCE. 



Chemistry and Physics. — On the Combustion of Carbon monoxirto and 0.\ 

 L. M —On the Combustion of Cyanogen, Dixon: < >n the so- 



Critical Pressure in Solid-, v. Riohter. L60. — Studies from the Lai 

 Pays p the 



Yea 'EN, 161. 



Geoloy . — Geolofti 



canic Eruption in New Zealand, 162. — New Minerals, A. Weibbaoh, 

 The Zoetrope applied to 11. Kick ■ 



Sketch of the Flora ot South Africa. II. BOLUS, 164 

 the Gallery of Marianne North's Paintings of Plants and their Hoi 

 Kew, W. B. Hemsley: Official she Museu 



tew: Filippo Parlatore, Flora Italians, T. Cai 

 i \n-\ : HO intarum. ! 



p. 77. 11 1. from t enland 



