To explore the upper atmosphere man first used kites, then balloons, then aircraft. For many years balloons were the most effective means of obtaining direct measurements in the stratosphere. But they... This description may be from another edition of this product.
ThriftBooks sells millions of used books at the lowest everyday prices. We personally assess every book's quality and offer rare, out-of-print treasures. We deliver the joy of reading in recyclable packaging with free standard shipping on US orders over $15. ThriftBooks.com. Read more. Spend less.