MaryamðŸŽ
@mry
After the First World War, the military has a strong interest in using Respiratory masks showed as a defense mechanism against chemical warfare. This in turn led to the development of efficient and inexpensive filters in the 1930s that were made with resin-injected dust. Further developments led to filters made of very fine glass fibers that could remove particulate matter while providing little resistance to breathing.ðŸŽ
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fereshte7428🎩🔵🔮
@7428
Why does the baby's nose look like an elephant's trunk in the picture?
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