viii CONTENTS 



CHAP. PAGE 



Half-herring-bone displaces the Full-herring-bone 

 The Depths of Cuts Height of Tapping Cleaning and 

 Marking of Tapping Area The Basal V Method 

 Gallagher's Opinion of it The Single Oblique Cut 

 Tapping one Section Daily better than Tapping two 

 Sections on Alternate Days Single Oblique Cuts on One- 

 third Sections in Ceylon Few Cuts Best Evils of 

 Over-tapping Especially where Trees are Closely- 

 planted Mr Skinner's Experiments with Various 

 Systems Plans for Rotation with Broad V (Basal V) 

 and Single Oblique Cuts Heneratgoda Experiments on 

 Frequency of Tapping A Magnificent Yield with 

 Moderate Tapping Need of Experiments with Larger 

 Number of Trees Daily Task of Tapping Coolie Clean- 

 liness Tapping Costs Errors in Lopping off Lower 

 Branches to help Bark Renewal in Closely-planted Areas 

 Fetch's Observations Renewal of Bark and Distance 

 in Planting Cutting-out Poor Yielders Leaving Seed 

 Trees Untapped Need of Unplanted Land Best Time 

 for Tapping Checking the Roll Number of Trees 

 Tapped per Coolie Disadvantages of Excessive Tasks 

 Supervision by Assistant Best Yielding Months. 



XXII. TAPPING-KNIVES AND UTENSILS 175 



The Ordinary Gouge and the Jebong Knife Other 

 Knives Attention to Coolies' Preferences Care of 

 Knives Latex Cups : Coconut Shells, Enamelled Iron, 

 Glass, Porcelain, Aluminium Care of Cups when not in 

 Use Spouts Latex Buckets Latex Carriers Light 

 Railways Decauville System Mono-rail Wire-rope 

 Carriers. 



XXIII. MOTIVE POWER . 182 



Suction-gas Engines Oil Engines The Hornsby Engine 

 The Diesel Engine Surplus Power Advisable Water 

 Turbines The Loss of Power with Water-wheels. 



XXIV. MACHINERY AND MANUFACTURE . . . .184 



The Poetry of Machinery Elemental Nature in the 

 Machine Inspiration to the Assistant Washing-mills 

 Width of Rollers Their Speed Depth of Grooves 

 Orientation of Mills Their Foundations Their Order 

 Position of Macerator in Factory Its Action on 

 Rubber The Loss in Weight it Causes The Creping- 

 mill The Mill for Finishing Crepe Chilled and Cast- 

 iron Rollers Treatment of Lump-rubber Of Sheet- 

 rubber The "Angle" Roller Mill The "J.A." Type 

 Gearing and Speed of Shafting Blocking Rubber 

 Worm and Strip Rubber The massing together of 

 Scrap, Cup-washing, Bark-shavings and Earth-rubber 

 Preliminary Steeping of such Rubber The " Universal" 

 Washing-machine Grading of Rubber Three Grades 

 generally sufficient First-latex Rubber Second-grade 

 Earth-rubber Effort to increase First-latex Rubber 

 A High Standard for Second-grade Rubber Lessening 

 Scrap-rubber Factors affecting Amount of Bark -shav- 

 ing Rubber The Relative Proportions of Grades Smok- 

 ing and Grading Blanket Crepe Need for an Extra 

 Mill and Spare Rollers Output of Mills Overworking 

 of Crepe-rubber Best Methods of Driving the Mills 

 Purity of Water Protection of Rubber from Sunlight. 



