54 



American Fisheries Society. 



rapidly and destroys the line quickly during the test. An oily 

 or soapy preservative has the opposite effect of diminishing 

 abrasion. 



During the test, considerable heat is developed at the point 

 of abrasion, which for one cause or another may vary and bring 

 about disagreement in the results. 



Overlooking the fluctuations caused by these things, we see 

 that, in general, the results confirm and amplify conclusions 

 already reached. Lines preserved with the following preserva- 

 tives reach, before the conclusion of the period of exposure, such 

 a state of disintegration that they will not stand any wear on 



2S0 

 260 

 240 

 220 

 200 

 180 



lO 



g 160 

 a: 



^ 140 

 o 



£ 120 

 § 100 



e 



6C 



40 

 20 



2 3 4 



MONTHS tXPOSED 



Fig. 8. — Wearing quality of lines exposed in sea water at Beaufort, N. C. 



the machine : untreated lines, pine tar. Bull's method. Petroleum 

 Products Nos. 1 and 2, and Gilsonite. Those which come out 

 best in the end are the copper oleates, which take first and sec- 

 ond places, followed by a copper paint. We may account for 

 the superiority of copper oleate by (1) the fact that the fibers 

 are effectively preserved against decay, and (2) the preservative 

 itself is of a soapy consistency, which lubricates the fibers. 



