BLAST OF BOMBS

Gisborne Herald, Volume LXVII, Issue 20378, 15 October 1940, Page 7

BLAST OF BOMBS

UNEXPECTED EFFECTS RESEARCH IN BRITAIN (British Official Wireless.) RUGBY, Oct. 12. Bursting German bombs over Britain have forced the special use of the word “blast” into the language, and for the last five weeks, particularly in London, the strangely unpredictable effects of "blast,” noticeably on glass windows in the districts affected, has been an absorbing topic of conversation. Experimental work carried out in the last few weeks by the Civil Defence Research Committee, with the aid of delicate apparatus, has upset many preconceived beliefs. “Blast” is not so terribly destructive as is generally held, but that is only because the effects are very local. It creates in the immediate vicinity of the explosion a wind six times as violent as a tornado, credited in America with an air speed of SQO miles an hour, but the wind, which is really gas from the bursting explosive, is very short-lived. Fades Away Rapidly Beyond a distance of 30ft. from the burst of an ordinary bomb of 5001 b. weight it fades away rapidly, and at 50ft. is almost innocuous as far as the destructive effect on buildings is concerned. Splinters from bursts will still have a velocity of 4000 ft. a second at 50ft., nearly four times the speed of sound. Within a radius of 10yds. a blast exerts its full force, and from the point of view of effect everywhere in that circle counts as a direct hit. “Blast" alone, however, is not believed to be lethal, except at very close range. It might kill through shock to the heart or the lesions of the lungs owing to the mouth having been closed, but not through the mere velocity of the gas. One of the most curious “blast” effects was) seen when a bomb struck a block of flats in London some days ago. It cut the building in two, with the result that people in the street could see half of two bedrooms, with the beds undamaged, but perilously near the edge.