Not content to let it burn by natural draught, he would blow it with his own breath, would expose it to the prevalent wind, would urge it with a fan, and would devise the first crude valveless bellows, perhaps the pigskin already familiar as a water-bottle, of which the psalmist says: I am become as a bottle in the smoke." [Please select]
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This may be described as a valveless air-pump. [Please select]
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