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. Bell telephone magazine . are available, and either may for maintenance and future additionsbe used—depending on the con- to the plant. ditions. Then comes the problem of de- Where aerial cable is involved, it tailed design of the aerial structureis, of course, necessaryto determine and spec-ify the size of support-ing strand for the vari-ous span lengths andunder the wind and iceloading likely to be en-countered. TOLL The engineeringproblems involved inthe construction of atoll aerial line or a tollunderground or aerialcable start with studiesof current requirementsand determination ofthe g
. Bell telephone magazine . are available, and either may for maintenance and future additionsbe used—depending on the con- to the plant. ditions. Then comes the problem of de- Where aerial cable is involved, it tailed design of the aerial structureis, of course, necessaryto determine and spec-ify the size of support-ing strand for the vari-ous span lengths andunder the wind and iceloading likely to be en-countered. TOLL The engineeringproblems involved inthe construction of atoll aerial line or a tollunderground or aerialcable start with studiesof current requirementsand determination ofthe general route to befollowed. Next come a detailedsurvey of the territoryand consideration ofvarious alternative ar-rangements that might be used. For example, „, ,. , /• , • ^ ,, , ^ , , .,,. the m f rl f <■ 1 ne steeljramework of this Oakland^ CaL, building, being . I e r u e constructed to house toll switching equipment, is designed might be over the top with special bracing to withstand extraordinary stresses. i88 Bell Telephone Magazine AUTUMN
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Keywords: ., bookauthoramerican, bookcentury1900, bookdecade1920, bookyear1922