at the not need to he supplied by sea (isotherms, etc.), the outside air pumps, but have isobars at 5,000 meters (16,- a system whereby the re- 405 feet), and, if possible, spired air is purified and at 1,000 meters (3,281 feet), the necessary elements etc., by making use of the added to it, so… … REGISTRATION BALLOONS IN ITALY,
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