64 



American Fisheries Society. 



The following tabular record gives a statement of the ex- 

 ternal condition of the lines after the fourth month at Beaufort : 



Table IX. — Condition of lines after fourth month tested for fouling. 



Symbol 



Treatment 



Condition 



A 

 F 

 G 

 H 

 I 



J 

 L 



M, N, O, P 



Q.R 



s 



X 



White line ; no treatment . 



Coal tar 



Pine tar 



Pine and coal tar 



Bull's method 



Petroleum product, No. 1 . 



Dutch method 



All copper oleate 



Copper paints 



Gilsonite 



Petroleum Product, No. 2 



Disintegrated and gone. 



Fouled with hydroids and barnacles. 



Do. 



Do. 



Covered with dense matting of hyd- 

 roids. 



Do. 



Few hydroids; nearly clean. 



Substantially clean ; very few barnacles ; 

 no hydroids. 



Perfectly clean; no growths. 



Fouled with hydroids and barnacles. 



Fouled, less than Petrolevmi Product, 

 No. 1. (This sample had been in 

 water only 1 month.) 



The conclusion to be reached in this section is that copper 

 oleate and copper paint are the only preservatives among those 

 tried that prevent growth of attaching organisms on the line. 

 The Dutch method reduces, but does not prevent such growths. 



LABOR AND TIME REQUIRED FOR APPLYING PRESERVATIVES. 



Some preservatives that might answer well some of the re- 

 quirements of a good material, are out of the question because 

 of the labor and time required to apply them. The laboriousness 

 of the application of tar, the time it takes to dry, and the fact 

 that it is a black, sticky nuisance, have caused many a net to go 

 unpreserved. When labor and time are expressed in terms of 

 expense, it will be found expensive, also. In this way cheap 

 preservatives may in the end turn out to be the most expensive. 



