CONTENTS. 



PAGE 



Chapter I i 



Introductory. Position and size of the island. The submarine Santa Cruz. 

 Outline of the island. Surface Western Oblong, Eastern Triangle, Intervening 

 Neck. The two rock-formations of the island. 



Chapter II 9 



The Limestone and Marl Formation in the Central Slope. Lenses. Foraminif- 

 erous shells. Contributors to the sea-sand of the submarine Santa Cruz. Con- 

 tributors to the Limestone Formation. Thinning out. Conclu.sions from 

 foregoing observations. Slope of the beds, outcrop, strike, dip, clinometer. 

 Use of the compass. How to find the synclinal axis. 



Chapter III 24 



The Limestone and Marl Formation outside of the Central Slope. The anti- 

 clinal axis of the Mt. Eagle Ridge. The Kingshill Range. The four smaller 

 hills. The limestone formation in the plains. The West End strata. Irregulari- 

 ties, faults. Thickness of the Limestones and Marls. Beach and reef limestones. 



Chapter IV 34 



The Blue-beach or indurated-clay formation. Nature and origin of the strata. 

 Their crystalline character. High dips. Relative positions of the two forma- 

 tions. The limestones and marls resting uncomformably on the blue-beach 

 strata. Deposition of the strata in the sea. Limestone beds of the blue-beach 

 formation. Waiter's Point and its fossils. Conglomerates. Travertine. The 

 variolitic structure. Jointing. Cleavage in the slate beds. 



Chapter V 44 



Arrangement of the blue-beach rocks. Dips classified. Arrangement of the 

 rocks in the Western Oblong. The anticlinal of the Northwest and its axis. 

 Synclinal axis of the Northwest. Strata of the Eastern Triangle , their anti- 

 ' clinals and synclinals. Contortions. Summary. 



Chapter VI 53 



The Igneous Rocks. Dykes and masses of trap rock. 



Chapter VII 57 



Minerals. 



Chapter VIII 61 



The Sculpturing of the island. Action of the sea on cliffs and bays. Rains and 

 streams. Preparatory action of the atmoiphere. Formation of valleys. Effect 

 of hardness in the strata. How heavy blocks move down the hillsides. Forma- 

 tion of plains. Immensity of geological periods. 



Chapter IX 7 



Connection of the foregoing with the physical geography of the island. Origin 

 of the hill ranges. The valley through the Christiansted Hills. Probable 

 arching of the strata of the Central Slope towards northeast. The Central and 

 Southwestern Plains. The Lagoons. The forms of the Valleys. 



