CONTENTS 



Page 



Foreword iii 



Elemental composition of meteorites 1 



Mineral composition of meteorites 1 



Chemical composition of meteorites 15 



External and internal features of meteorites 17 



Chondrule, its nature and origin 29 



Origin of other types of structure in meteoric stones 39 



Metamorphism in meteorites 40 



Meteorites compared with terrestrial rocks 45 



Tektites 47 



Combustible meteorites 48 



Chondritic structures in terrestrial rocks 51 



Methods of analyses of stony meteorites 57 



LIST OF PLATES 



Frontispiece. George Perkins Merrill. 



Plate 1. External form of Allegan and Bath Furnace stones; and of Mazapil 

 iron. 



2. (1) Carbon nodule in Canon Diablo meteoric iron; (2) Re-fused feld- 



spar in Estherville meteoric stony iron. 



3. (1) Maskelynite in Troup meteoric stone; (2) Merrillite in New Con- 



cord meteoric stone. 



4. (1) Fragmental twinned pyroxenes in .Johnstown meteorite; (2) Frag- 



mental pyroxenes in Estherville meteorite. 



5. (1) Widmanstatten figures, enlarged; (2) Schreibersite in Arispe and 



(lower) in Tombigbee irons. 



6. (1) Meteoric iron from Dungannon, Va., showing partial granulation; 



(2) The same greatly enlarged. 



7. (Upper) Swathing kamacite in Admire pallasite; (lower) Octahedral 



structure and Reichenbachian lines in Carleton iron. 



8. (Upper) Neuman lines in Braunau iron; (lower) Granular structure in 



Mejillones iron. 



9. (Upper) Octahedral iron with silicate inclosures, Four Corners, 



N. Mex.; (lower) Persimmon Creek, N. C, iron. 



10. (Upper) Brecciated hexahedrite, Kendall County, Tex.; (lower) 



Coarsest or kamacite octahedrite, Ainsworth, Nebr. 



11. (1) Swollen kamacite in Mesa Verde iron; (2) Structure of Four Corners 



iron, enlarged; (3) Quartz crystals in St. Marks stone; (lowest) 

 Chondrules in Sharps, Va., stone. 



12. Grahamites from Morristown and Crab Orchard stony irons. 



13. (Upper) Estherville stony iron; (lower) Same with inclosure. 



14. Pallasite from Brcnham, Kans. 



15. (Upper) Section of the Admire pallasite; (lower) An iron-rich portion 



of Brenham pallasite. 



16. Microstructure of (1) El Nakhla stone and (2) of the Shergotty stone. 



