CONTENTS 1
Lesson 1 Text：Power 1
Supplementary Reading: 8
Ⅰ．Power and Horsepower 8
Ⅱ．Force and Work 9
Lesson 2 Text：Pulleys and Belts 11
Supplementary Reading: 19
Ⅰ．Belts and Pulleys 19
Ⅱ．The Lever 21
Lesson 3 Text：Mechanized Farm Work 22
Supplementary Reading: 29
Ⅰ．Preface to"Farm Machinery and Equipment"（Extracted） 29
Ⅱ．Crops vs Farm Machinery 30
Lesson 4 Text：Gears 32
Supplementary Reading: 40
Ⅰ．Gear Types 40
Ⅱ．Driving Shaft 41
Lesson 5 Text：Lubrication 43
Supplementary Reading: 52
Ⅰ．Friction and Lubrication 52
Ⅱ．Bearings 53
Lesson 6 Text：Pioneer Farm Machines 55
Supplementary Reading: 64
Ⅰ．Field Power 64
Ⅱ．From Hand Farming to Power Farming 65
Lesson 7 Text：Internal-combustion Engine 67
Supplementary Reading: 74
Ⅰ． Gasoline and Diesel Engines 74
Ⅱ．Wankel Engine 75
Lesson 8 Text：Changing Concepts 77
Supplementary Reading: 86
Ⅰ．Basic Functions of Tractors 86
Ⅱ．Tractor Types 87
Lesson 9 Text：Any Progress on Farm Vehicle Automation? 89
Supplementary Reading: 96
Ⅰ．Safety Requirements for Automatic Vehicle Control 96
Ⅱ．Tomorrow's Combine 97
Lesson 10 Text：Electric Motors for the Farm 99
Supplementary Reading: 106
Ⅰ．Induction Motors 106
Ⅱ．Electric Power on Farms 107
Lesson 11 Text：Hydraulic Pumps 110
Supplementary Reading: 120
Ⅰ．Hydraulics 120
Ⅱ．Hydraulic Press or Jack 121
Lesson 12 Text：The Art of the Crawler Driver 124
Supplementary Reading: 133
Ⅰ．Tracklaying Tractors 133
Ⅱ．How to Avoid Danger on the Slopes 134
附录 136
Ⅰ．英译汉中的几个问题 136
Ⅱ．总词汇表 158