192 



MOSQUITO ERADICATION 



In oiling such growths, it sometimes happens that nearby 

 portions of the pond, lake or stream may be used for bathing or 

 other purposes for which oil would be objectionable. In such 

 cases, the oil required to deal with the aquatic growths must be 

 prevented from escaping to other parts of the water surface. 



1 



Fig. 136. Fig. 137. Fig. 138. 



Fig. 136. — Section of Ziomsen subaqueous saw, slightly reduced in drawing. 

 Fig. 137. — Section of improvised saw of "licker-in" wire, showing method 

 of joining. 



Fig. 138. — Section of "licker-in" wire, slightly reduced in drawing. 



;> 



This is best accomplished by running a boom about the area in 

 which it is desired to confine the oil. 



These booms may be made of logs tied together and to the shore 

 or of boards, which are preferable, owing to their straightness and 

 lesser liability to become water-logged and sink, thus allowing the 

 oil to get out. 



