File:Bell telephone magazine (1922) (14753978834).jpg

Identifier: belltelephonevol21mag00amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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OMBS may use any one of sev-eral incendiary agents, with magne-sium most commonly employed so far.The magnesium bomb, with its light-ness of weight and intensity of heat,best fulfills the enemy objective ofsimultaneously starting the most fires,on account of the possible concentra-tion of a great number of the smallestsized bombs in the limited carryingcapacity of an airplane. The magnesium bomb most gener-ally used to date, weighing a little overtwo pounds, would not be able to pene-trate the usual reinforced concrete orhollow tile roof on a fire-resistive tele-phone building. It would, however,pierce any ordinary roof of slate ortile on wood sheathing, and land onthe floor below unless it should strikea beam or other roof member. In theusual case of a fire-resistive structure,the bomb would come to rest on a flatroof and burn itself out if left undis-turbed. The only measurable dam- f 942 Protecting the Service Against Fire 179 Right: Water sprayspeeds combustion rela-tively quietly
Text Appearing After Image:
Left: A full stream of water does a quicker but explosive job Two Methods of Extinguishing Magnesium Bombs age, it is expected, would be to the tarand gravel roofing or insulation wherethis type of finish is used. It is to theroofs which are not fireproof, and alsoto nearby buildings, that special atten-tion would have to be directed. Sky-lights, which are not very common intelephone buildings, have receivedspecial consideration, in many casesbeing eliminated in favor of a rein-forced concrete slab. The magnesium bomb, on accountof its shape and light weight, has rela-tively poor directional characteristics,and the bombs have a tendency tospread out as they fall. It is interest-ing to note that this type of bomb at-tains its maximum velocity after drop-ping a mile, beyond which its speed is uniform. Where better aim at stra-tegic targets is an important factor,such as warehouses, docks, factories,or munitions stores, heavier bombs ofequivalent construction and rangingup to more than 5

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