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



Protection Expeeiments. 



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. 



Odor 



Color. 



Consistence. 



Weathering 

 condition. 



A- 



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 



Slightly oily 

 or var- 

 nishy. 



Oilv 



Dark brown, 

 nearly black. 



YeUowish brown 

 Lemon yeUow... 



Light yellow 



Yellow brown... 



Brownish yeUow. 



Dirty white 

 where thin. 



YeUow to dark 

 brown. 



Nearly black 



Dark brown 



MUky white 



Dirty white 



Colorless 



do 



Firm where thinly 

 appUed, soft where 

 thickly appUed. 



Flaky and crumbly... 

 Soft and pliable 



Soft and fairly pUable, 

 smooth. 



Soft and fairly pliable. 



SUghtly greasy, flaky. 



Soft 



Does not hold evenly; 

 has dried out and har- 

 dened, except where 

 heavUy appUed. 



Very Uttle grease left. 



B- 



SUghtly oUy. 

 Oily 



Holds well, has not de- 

 teriorated. 

 StUl greasy, holds evenly. 



C 



Slightly oily.. 

 Oily 



has deteriorated, but is 

 best of greases. 



Holds weU; has deterior- 

 ated more than B . 



Some grease in heavy 





do 



do 



Musty 



do 



Tallowy 



do 



SUght par- 

 affin. 

 do.... 



portion, flaky at ends. 

 Not as good as B and C, 



D 



Firm but pliable, not 



flaky. 

 Fairly soft 



but better than A; has 

 deteriorated consider- 

 ably. 



Fairly even where thin; 

 some grease remains. 



Has hardened somewhat. 



E. 

 F 



Powdery, no grease 

 left. 



Soft and pliable 



Firm 



Badly deteriorated. 



Like day of appUcation. 

 Holds weU, especiaUy 



G- 



Firm but pUable 



Soft and even 



where thick. 

 Like day of appUcation. 



Very good. 



H 



Strong naph- 

 thaline. 



NaphthaUne. 



No odor 



do 



Creamy yeUow.. 



YeUowish white. 



Dark brown 



do 



Hard, waxy, flakes 

 ofl where thinly ap- 

 plied. 

 Like firm laundry soap 

 Firm, uneven 



Appears very good. 



Very good. 



Some deterioration. 



l| 



Firm, hard, waxy 



Hard where thin, 



sticky where thick. 



do 



Poor. 



A 



Tarry 



do 



Nearly black 



do 



Like day of appUcation. 

 Has changed very Uttle. 



i 



No odor 



....do 



Black 



Hard and smooth, 

 velvety. 

 Firm and even 



Like day of appUcation. 



kI 



Velvety black. . . 



Slight deterioration. 



weather aifected 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 



