ELECTRICITY. 495 



ed^Leyden phial*; then lift up the piece of paper by one 

 corner, and holding it suspended, project upon it the 

 mixed powder of dragon's blood and gum arabic, by 

 means of the elastic gurn bottle. The configurations in 

 this case are very beautiful, and may be made in various 

 shapes, such as letters, stars, stripes, &-c, by moving the 

 knob of Dhe Leyden phial in the desired direction ; but 

 they are of one color ; viz. red, for the gum arabic beititf 

 nearly of the color of the paper, cannot be distinguished 

 upon it. If the paper thus painted be held very near to 

 the fire during a few seconds, the powder of dragon's 

 blood being a resinous substance, will be melted, and 

 will be fastened on the paper ; after which the powder of 

 gum arabic may be wiped off with a handkerchief. 



' Powders of other colors may be projected upon the 

 paper, after the same manner, but unless they are of a 

 resinous nature, so as to be easily melted by heat, it is 

 very difficult to fasten them to the paper. In these ex- 

 periments the Leyden phial must not be charged too high 

 nor too low ; for in the former case, the figure will be too 

 confused and irregular, and in the latter it will be too 

 faint. In order to form a neat and determinate figure, 

 and to leave the rest of the paper clean, the powders 

 must not be projected perpendicularly to the paper, but 

 the stream must be thrown in a direction parallel to the 

 surface of the paper. It is also necessary to perform 

 these experiments in as expeditious a manner as possible ; 

 for, if the paper be suffered to cool too much, or the 

 electricity to dissipate, the desired effect cannot be ob- 

 tained.' 



12. The fying feather or the electrical shuttlecock. 

 Take an excited glass tube in one of your hands, and 

 let a small light feather be left in the air, at the distance 

 of about eight or ten inches from the tube. This fea- 

 ther will be immediately attracted by the tube, and will 

 adhere very closely to its surface during a few seconds, 

 and sometimes longer; then, having acquired the same 

 sort of electricity, it will be repelled, and by keeping 

 the tube under it, the feather will continue to float in the 

 air at a considerable distance from the tube. By man- 

 aging the tube dexterously you may drive the feather to 

 any part of the room at pleasure. 



