It was only discovered by scientists in modern times that the air actually has weight. This passage in Job, however, written thirty-five or more centuries ago, indicated that the two great terrestrial fluids of air and water forming earth's atmosphere and hydrosphere are both "weighed" by God's careful "measure" to provide the right worldwide balance of forces for life on earth.
Another remarkable "weighing" act of God is noted in Job 37:16. "Dost thou know the balancings of the clouds, the wondrous works of him which is perfect in knowledge?" Clouds are composed of liquid drops of water, not water vapor, and water is heavier than air, so how are they "balanced" in the sky? "For he maketh small the drops of water: they pour down rain according to the vapour thereof: Which the clouds do drop and distill upon man abundantly" (Job 36:27-28).
Meteorologists know that the weight of the small water droplets in the clouds is "balanced" by the "weight of the winds"--air rushing upward in response to temperature changes. Eventually, however, the droplets coalesce to form larger drops which overcome these updrafts and fall as rain. "By watering he wearieth the thick cloud" (Job 37:11). The coalescence is probably triggered electrically in the clouds themselves, "when he made a decree for the rain, and a way for the lightning of the thunder" (Job 28:26).
Although these verses are not couched in the jargon of modern science, they are thoroughly scientific and up to date. "Lo, these are parts of his ways: but how little a portion is heard of him? but the thunder of his power who can understand?" (Job 26:14). HMM http://www.icr.org/article/6136/