755. What is the amount of water pressure?
The pressure of the sea, at the depth of 1,100 yards, is equal to 15,000 lbs. to the square inch.
"But the land, whither ye go to possess it, is a land of hills and valleys, and drinketh water of the rain of heaven."—Deut. xi.
756. What element is the most abundant in nature?
Oxygen, which forms so large a part of water. Of animal substances, oxygen forms three-fourths; of vegetable substances it forms four-fifths; of mineral substances it forms one-half; it forms eight-ninths of the waters and one-fifth of the atmosphere; and aggregating the whole creation, from one-half to two-thirds consists of oxygen.
757. In what ways does man use oxygen?
Man eats, drinks, breathes, and burns it, in various proportions and combinations. It is estimated that the human race consume in those various ways 1,000,000,000 lbs. daily; that the lower animals consume double that amount; and that, in the varied works of nature, no less than 8,000,000,000 lbs. of oxygen are used daily.