38 BULLETIN 1107, U. S. DEPARTMENT OF AGRICULTURE. 



Pkotection Experiments. 



Steel sleeves. — To determine the protective value of steel sleeves 

 placed around the cables within the suspension rings a number of 

 these were placed on a commercial cable at Palo Alto. As no attack 

 was made on the cable in that locality the results are negative. 



P. & B. paint. — Many of the old cables used in the city of Santa 

 Barbara have been coated with P. & B. paint. In numerous cases 

 this paint gathered on the underside of the cables, which allowed the 

 beetles to obtain a foothold for boring from it. 



Weathering Tests of Protective Materials. 



Table 6 gives a list of materials which might be used on the cables 

 to keep the beetles from boring into them. It also shows how the 



Table 6. 



-Weathering tests of materials applied to cables for protection against 

 the lead-cable borer; Los Gatos, Calif., 1920-21. 



Ma- 

 terial 



Date 

 examined. 



Nov. 30, 1920 



Nov. 24, 1921 

 Nov. 30, 1920 



Nov. 24,1921 



Nov. 30, 1920 

 Nov. 24, 1921 

 Nov. 30, 1920 



Nov. 24, 1921 



Nov. 30, 1920 

 Nov. 24, 1921 



Nov. 30, 1920 

 Nov. 24, 1921 



Nov. 30, 1920 



Nov. 24, 1921 

 Nov. 30, 1920 



Nov. 24, 1921 

 Nov. 30, 1920 

 Nov. 24, 1921 

 Nov. 30, 1920 



Nov. 24, 1921 

 Nov. 30, 1920 



Nov. 24,1921 



Odor 



Slightly oily 

 or . var- 

 nishy. 



Oily 



Slightly oily. 



Oily. 



Slightly oily.. 



Oily 



do 



Color. 



Consistence. 



Dark brown, Firm where thinly 

 nearly black. applied, soft where 

 thickly applied. 



YeUowish brown Flaky and crumbly... 

 Lemon yellow. - . Soft and pliable 



Weathering 

 condition " 



Light yellow Soft and fairly pliable, 



smooth. 



Yellow brown.. ' Soft and fairly pliable 



.do. 



Mustv. 

 ....do. 



Tallowy . 



Slightly greasy, flaky. 

 Soft 



Brownish yellow 



Dirty white 

 where thin. 



Yellow to dark Firm but pliable, not 

 brown. 



Nearly black Fairly soft 



Dark brown Powdery, no grease 



left. 



Milky white Soft and pliable 



Firm. 



do i Dirty white 



Slight par- Colorless 



affin. 

 do do 



Strong naph- Creamy yellow. . 

 thaline. 



Naphthaline. Yellowish white. 



No odor Dark brown 



do do 



Tarry Nearly black — 



do do. 



No odor Black. 



Firm but pliable . 



.do. 



Velvety black. . 



Soft and even 



Hard, waxy, flakes 

 off where thinly ap- 

 plied. 



Like firm laundry soap 



Firm, uneven 



Firm, hard, waxy 



Hard where thin, 

 sticky where thick. 



do 



Hard and smooth, 

 velvety. 



Firm and even 



Does not hold evenly; 

 has dried out and har- 

 dened, except where 

 heavily applied. 



Very little grease left. 



Holds well, has not de- 

 teriorated. 



Still greasy, holds evenly, 

 has deteriorated, but is 

 best of greases. 



Holds well; has deterior- 

 ated more than B. 



Some grease in heavy 

 portion, flaky at ends. 



Not as good as B and C, 

 but better than A; has 

 deteriorated consider- 

 ably. 



Fairly even where thin; 

 some grease remains. 



Has hardened somewhat. 



Badly deteriorated. 



Like day of application. 

 Holds well, especially 



where thick. 

 Like day of application. 



Very good. 

 Appears very good. 



Very good. 



Some deterioration. 



Poor. 



Like day of application. 



Has changed very little. 

 Like day of application. 



Slight deterioration. 



weather affected them. The test cable was placed in position Septem- 

 ber 29, 1920, and thoroughly examined November 30, 1920, and No- 

 vember 24, 1921. The materials to be tested were placed on the cable 

 at the points where it was suspended by the rings. The tallow and 



