448 Intelligence and MiscellaneoiLS Articles. 



conclusive experiments, we shall describe some new observations 

 which appear to us to be adapted to prepare gradually for the solu- 

 tion of the question. 



1, We have endeavoured to obtain effects analogous to the lumi- 

 nous stratifications, by causing induced and ordinary electricity to 

 act upon light and moveable conductors, perceptibly obeying the 

 known laws of electrical influences. 



A plate of glass, 2 centims. in breadth and 15 centims. in length, 

 was sprinkled with powdered coke, and the two ends of the induced 

 wire were caused to act upon the two extremities. Under the con- 

 ditions indicated, the powder is seen to arrange itself all along the 

 plate in transverse lines distinctly separated from each other by in- 

 tervals of 2 to 3 milUms. The appearance of these lines varies, like 

 that of the stratifications, by the influence of an armature applied 

 against the glass, and according as the dischai'ges take place by con- 

 tact or by sparks. We obtain similar bands with ordinary electricity ; 

 and account for the formation by the propagation of tlie electricity 

 through the conducting powder, and by the mutual repulsion of the 

 particles. 



The induction spark is much elongated, and appears perfectly 

 striated by brilliant and obscure points arranged lilie a necklace, 

 when it is caused to shoot into the air after having shaken the pow- 

 dered coke. 



Transverse stratifications of the same kind occvir in tlie discharge 

 across a smoky flame. At the apex of a flame of turpentine, the 

 brilliant points are sometimes replaced by so many little distinct 

 flames. 



2. With the view of understanding the effects of external con- 

 ductors, we placed flames between the two plates of a condenser, 

 setting the lateral conductors in action likewise. The plates were 

 charged by the electrical machine ; the flame sank, became widened 

 and sometimes bifurcate, the lateral conductors attracted it ; it was 

 also seen to elongate itself in a dart in two opposite directions. 

 These circumstances agree with the effect produced by the hand 

 brought near a vacuum-tube in which a flood of continuous light is 

 made to pass ; a portion of this flood is attracted by the hand against 

 the wall, and another portion becomes concentrated towards the 

 axis and stratified. 



We have reproduced, with the electrical machine, a result 

 that we had already observed with the induction apparatus. A 

 cylindrical vacuum-tube being occupied by a flood of continuous light, 



phenomenon. We have found that they may even suppress the bauds. 

 Thus by isolating one of the electrodes, and placing the other in contact 

 with one end of the induced wire, by the intermedijition of a column of 

 water, we may obtain at pleasure bands and a continuous flood of light ; 

 by placing one of the electrodes in contact with one end of the wire and 

 drawing the sjiarks from the other side, with the intervention of a greater 

 or less resistance, we may substitute the continuous flood for the bands of 

 the negative side, of the ])osltive side, or of the whole length of the tube. 

 The changes of tension may account for these effects. 



