M. W. Holtz on a new Electrical Machine. 429 



in the latter, on the other hand, an inverse deportment prevails, 

 for the tension of the free electricity on the glass surface is neces- 

 sarily higher than that which results from its inducing action. But 

 since both currents traverse the same conductor, and one is only 

 a consequence of the other, the cessation of the one must follow 

 the cessation of the other, and the greatest striking- distance of 

 the primary current is at the same time that of the apparatus. 



If one of the conductors is connected with the earth, it is only 

 after exceeding this striking-distance that the secondary current 

 can disappear, since the coating opposite to it can still electrify 

 the glass disk. In fact, without interrupting this current the 

 electrodes maybe removed to more than double the distance; 

 but this will very soon diminish with the charge of the coating, 

 since no more new electricity is added. 



If there is a jar in the circuit, both currents must simultane- 

 ously disappear when the charge has attained a definite amount. 

 The intensity on the coatings of the fixed disk sinks ; the jar allows 

 part of its charge to pass on to the rotating disk ; and as this, 

 after half a turn, passes to the opposite electrical coatings, in a 

 short time the machine begins to work in the opposite direction. 

 But the jar must in this way continually be charged and again 

 discharged. 



Without a jar, too, inversions of the current may occur, if the 

 maximum striking-distance is near, and the fixed disk is only 

 coated on its outside. The opposite electricity then collects on 

 the inside, which remains bound so long as there is a portion of 

 free electricity on the outside. If this latter is lost, either in- 

 tentionally or unintentionally, the latter begins to act induc- 

 tively in the opposite direction. It is very inconvenient, that 

 under these conditions the rotation can scarcely be interrupted 

 for a few seconds without, on beginning it again, the current 

 being found already in the opposite direction. 



By two simple arrangements the machine can be made still 

 more suitable for each special object. 



To keep up the action independently of the opening of the 

 circuit, it is necessary, as I have stated, to keep the currents 

 separate. The construction might easily be so altered that those 

 currents could only move in separate conductors ; but this would 

 do away with the possibility of using them together where it 

 was desirable to do so. It is rather advantageous to avoid the 

 separation until the primary current ceases ; and this is effected 

 as follows. 



Imagine a third conductor, which may be called g, parallel to 

 the others and at about a quarter of a turn from them, fastened 

 on the corresponding supports, and the coating marked — pro- 

 longed to its points and permanently joined with the conductor e. 

 As long as the striking- distance is within definite limits, both cur- 



