66 BULLETIN 440, U. S. DEPARTMENT OP AGRICTJLTUEE. 



flat, the pond is usually constructed by excavating the center and 

 building earth dykes on the low sides. In some instances a ditch 

 must be constructed for supplying water. 



For circular mills cutting from 30,000 to 40,000 daily, the usual 

 size of the pond is from one-half to one acre. For single-band mills 

 where storage is not an item, the ponds vary from 1 to 4 acres. The 

 size of ponds at double-band mills depends upon the possibilities of 

 each site and the desire of the operator to store logs for a run, of a 

 month or more in the fall. Such ponds range from 4 to 14 acres. 

 The usual capacity of a pond, excluding sinkers, is from two-thirds 

 to three-fourths of a miUion feet of logs per surface acre. Where 

 necessary, logs may be piled in a pond with an overhead trolley, 

 thus about trebling the capacity. The cost is, however, very large. 



The work upon a log pond may begin with unloading the cars, 

 and includes sortmg, raising sinkers, and delivering logs to the haul- 

 up. In the yellow pine of the eastern Sierras sinkers are practically 

 unknown, and the unloading is customarily done by the train crew. 

 The pond crew, therefore, consists of one man for a singls-band mill 

 and two men for a double-band mill. One man is stationed at the 

 lower end of the log slip to pole the logs into position for the hoisting 

 chain. The other man poles the logs to within reach of the first 

 and does sorting and general pond work. For a daily output of 

 120,000 the cost is about 5 cents per 1,000, which may be considered 

 the low figure for such work in good-sized plants. 



Since both sugar-pine and white-fir butt logs sink on bemg placed 

 in the water, provision must be made for raising sinkers from ponds 

 where these two species are logged. The simplest scheme is one 

 used at a double-band mill with a small pond. The log cars are 

 unloaded by a stationary overhead boom at a point very near the 

 log slip. A swinging boom with a steam winch and cable is located 

 on a crib work in the pond. After each train is unloaded, the sinkers 

 are picked up by tongs and swmig around by the boom to within 

 reach of the pikeman at the log sHp. The crew consists of two 

 pondmen dehvering logs to the slip, one man in a flatboat attaching 

 tongs to sinkers, and one winchman. One-third of the time of the 

 wmchman is devoted to unloading. The night crew contains only 

 the two pondmen. The total daily cost is therefore $17, which, dis- 

 tributed over 250,000 feet, is 7 cents per 1,000. 



At another operation, with a large number of sinkers, the cost of 

 pond work is still greater. The pond crew does the unloading, 

 using a winch located on a cribwork in the pond. The entire crew, 

 except one man, works at unloading, and the average time required 

 for an 18-car train is 20 minutes. The unloading is done at a point 

 some distance from the log slip. When not unloading, the crew is 

 at work raising sinkers, sortmg logs, and shifting logs to the mill end 



