570 Our Surroundings 



They examined several tons of this substance and finally succeeded 

 in extracting from the whole mass about one-half a teaspoon ful 

 of a substance which was many times more radioactive than 

 uranium. This substance, owing to its remarkable power of radia- 

 tion, was called radium. 



The discovery of radium is regarded as one of the greatest 

 scientific discoveries of the century. Its influence on the future 

 development of physics and chemistry cannot be over-estimated. 

 Honors and prizes for the discovery of radioactive elements were 

 awarded jointly to Madame Curie and her husband. Among the 

 honors was part of the Nobel prize for physics. 



In 1906 Pierre Curie was killed in an accident and Mme. Curie 

 succeeded him as professor of physics and director of the physical 

 laboratory at the Sorbonne. In 1911 she was awarded the Nobel 

 prize for chemistry. She died in July, 1934. 



The Wrights. While many scientists have had important 

 parts in developing aerial navigation and in giving us a certain 

 conquest of the air, undoubtedly special recognition should be 

 given to two brothers, Wilbur and Orville Wright, who built and 

 flew the first practical airplane. These brothers, one born in 1867 

 and the other in 1871, were interested from boyhood in flying 

 things. While still children, they experimented with a flying toy 

 and then with kites and that, by easy steps in the years that fol- 

 lowed, led them, through the construction of gliders, to the air- 

 plane. A bicycle shop, which they owned together at Dayton, 

 Ohio, supplied them with the funds necessary for experimentation 

 in their chosen field. 



They invented gliders sufficiently strong and well balanced 

 to remain in air and to support a passenger. They studied the 

 flights of birds, and the scientific experiments of men like Langley 

 whose discoveries had made ultimate success possible. 



From 1900 to 1903 the brothers continued experiments at 

 Kitty Hawk, N. C., with gliders and kites. Then, in December 

 1903, they finished their first power air machine, which actually 

 flew for 59 seconds. By degrees as improvements were worked 

 out, flights of longer duration followed, one lasting over an hour 

 and marked by a speed of over 40 miles per hour. 



