Please give some facts as to the capacity of balloons; what is used to fill them, and what are some of the greatest balloon performances?
L. J. Swartz.
Answer.—The buoyancy of a balloon depends on the weight of the gas with which it is inflated compared with the weight of common air, bulk for bulk. Hydrogen is the lightest of all known substances. A cubic foot of atmospheric air at a temperature of 34 degrees weighs 527.04 troy grains, while a cubic foot of hydrogen is about fourteen and a half times lighter than this. Coal gas is about two and a half times lighter than air. If a balloon would contain 1,000 pounds of atmospheric air at temperature of 34 degrees Fahrenheit, but filled with coal gas would weigh, all told—covering, gas, and appendages—600 pounds, it would rise with a force equal to the difference of these two numbers, or 400 pounds. Mr. Glaisher, not long since, constructed a balloon containing 90,000 cubic feet of coal gas, that carried 600 pounds, and rose to the unsurpassed height of 7½ miles, where the barometer, which stands at about 30 at sea level, sank to only 7 inches, showing an atmosphere of only about 22 per cent of the weight at sea level. The longest balloon trip on record is that of the late Professor J. Wise and Mr. La Mountain. Starting from St. Louis for New York City, they traveled 1,150 miles in a little less than twenty hours, when, being caught in a contrary current, they were compelled to desist. Mr. Lowe’s mammoth balloon was said to contain 700,000 cubic feet of coal gas and have a lifting power of 22½ tons; but it was badly constructed and accomplished nothing remarkable. In some 10,000 recorded ascents made since the Montgolfiers invented their famous balloons, just 100 years ago this year, there have been but fifteen deaths among 1,500 aeronauts; which indicates less danger in this business than is generally supposed.
JEFFERSON DAVIS.
Ferry, Mich.
1. Give a short biography of Jefferson Davis.
G. F. Page.
Answer.—Jefferson Davis was born in Kentucky in 1808; first became prominent in politics as a member of the House of Representatives, and later as Senator from Mississippi. He served in the Mexican war, having been educated at West Point. During President Pierce’s administration Davis was Secretary of War, and was said to rule both President and Cabinet. In 1857 he was returned to the Senate, where he remained until chosen President of the Confederacy in 1861. This office he held for four years. In 1865, after the fall of Richmond, Davis was captured and imprisoned in Fortress Monroe for two years; was released on bail in 1867, and finally liberated by the general amnesty, Dec. 25, 1868. He is still disqualified from holding any office of honor or emolument under the General Government.