(30 Vol. XLirr., Art. 5. 



CONTENTS. 



Page 



I. Introduction 1 



II. Tojxjgi'apln' 3 



III. General Geology 5 



(A) The Paleozoic Formation , 6 



(B) The Mesozoic Formation 10 



(C) DiQritic Rocks 12 



(D) Dyke Pvocks 19 



(E) Faults 27 



IV. The Veins in General 28 



V. The Ore-Bringer 36 



VI. The Copper-Tin Veins 38 



(1) The Deposition of the Muin Cnssiterite Ore 40 



(2) The Deposition of the Quartzose Wolframite-Cassiterite 



Ore 45 



(3) The Deposition of Chalcopjiite 48 



(4) The Dei^osition of Zincblencle 49 



(5) The Deposition of BaiTeu Quartz . . .• 49 



VII. The Alteration of the Clay Slate 50 



(A) Diopsiclization of the Slate 'J^^ 



(B) Chloritization of the Slate 50 



(C) Silicification of the Slate -jl 



( 1^ ) Epidotization of the Slate 52 



(E) Sideritization of the Slate 53 



V^III. Quartzose Veiulets cutting the Country Piock Adjacent to the 



Veins 55 



IX. Sumuiarv and Conclusions • • ■ 57 



Published May lOth, 1920. 



