NEW CONCEPTIONS IN SCIENCE 



German named Hittorf had observed some curious 

 actions which took place when the vacuum in the 

 well-known Geissler tubes was carried to a very 

 high degree. Most every one who likes to dab- 

 ble in scientific matters has seen the beautiful dis- 

 plays which take place when various chemical 

 substances, salts and minerals, are put into these 

 glass tubes of high vacuum and attached to an 

 electrical machine. Gorgeous colors result when 

 the tube is shot through with the electrical current. 

 Hittorf noticed that the same sort of an exquisite 

 glow, something like that which phosphorus gives 

 off in the dark, occurred when a current was put 

 through a tube containing no salts or other sub- 

 stances at all. The colors changed with the kind 

 of glass used, while the glow itself acted very dif- 

 ferently, according to how far the exhaustion of 

 the tube was carried. 



Men of science were immensely puzzled at this 

 unexpected apparition; it was as if a kind of 

 scientific ghost had stepped out from the wall. No 

 end of experimenting was carried on, but no great 

 headway was made until Sir William Crookes 

 turned his ingenuity as an experimenter to un- 

 ravel the matter. 



Crookes' first attack was to produce a vacuum 

 such as had never been dreamed of before. How 

 the earth's atmosphere weighs down upon its crust 



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