INTRODUCTION xiii 



carried on in New Zealand, with the result that the ladder dredge 

 was accepted as the best type for the purpose. Within a short time 

 the ladder dredge was introduced in Western United States for 

 gold mining, and to-day the dredges used in California are said to 

 excel all others in use for gold mining throughout the world. It 

 has only been within twelve years that the tailing stacker has been 

 used in connection with these dredges. This device has greatly 

 simplified the work and materially reduced the labor needed 

 to operate the machine. 



