Blanchard, Madame--gas balloon--_killed_. [Page 119] 1819. Gay Lussac--gas balloon, ascended 23,040 feet above the level of the sea. Barometer 12.95 inches; thermometer 14.9 Fah. " Gay Lussac and Biot--gas balloon for the benefit of science. Both philosophers returned safely to the earth. 1824. Sadler--gas balloon--_killed_. " Sheldon--gas balloon. " Harris--gas balloon--_killed_. 1836. Cocking--parachute from gas balloon--_killed_. 1847. Godard--Montgolfier balloon fell into and extricated from the Seine. 1850. Poitevin, a successful French aeronaut. " Gale, Lieut.--gas balloon--_killed_. " Bixio and Barral--gas balloon. " Graham, Mr. and Mrs.--gas balloon.--Serious accident ascending near the Great Exhibition in Hyde Park. " Green, the most successful living aeronaut of the present time. Of the 41 persons enumerated, 14 were killed, and nearly all the aeronauts met with accidents which might have proved fatal. [Illustration: Fig. 118. Flying machine (_theoretical_).] [Page 120] _Tenth Experiment._ Soap bubbles blown with hydrogen gas ascend with great rapidity, and break against the ceiling; if interrupted in their course with a lighted taper they burn with a slight yellow colour and dull report. _Eleventh Experiment._ By constructing a pewter mould in two halves, of the shape of a tolerably large flask, a balloon of collodion may be made by pouring the collodion _inside_ the pewter vessel, and taking care that every part is properly covered; the pewter mould may be warmed by the external application of hot water, so as to drive off the ether of the collodion, and when quite dry the mould is opened and the balloon taken out. Such balloons may be made and inflated with hydrogen by attaching to them a strip of paper, dipped in a solution of wax and phosphorus, and sulphuret of carbon; as the latter evaporates, the phosphorus takes fire and spreads to the balloon; which burns with a slight report. The pewter mould must be very perfectly made, and should be bright inside; and if the balloons are filled with oxygen and hydrogen, allowing a sufficient excess of the latter to give an ascending power, they explode with a loud noise directly the fire reaches the mixed gases. _Twelfth Experiment._ In a soup-plate place some strong soap and water; then blow out a number of bubbles with a mixture of oxygen and hydrogen; a loud report occurs on the application of flame, and if the room is small the window should be placed open, as the concussion of the air is likely to break the glass. _Thirteenth Experiment._