( 322 ) 



is more and more retai'ded, the regular form of \ho curve heint»' 

 retained. 



4. Tiial we mav form some opinion about tlie value of tiie time 

 constant 7' tliat is reqnii-ed in ^'ario^s circumstances in order to 

 reach the limit of aperiodicily, we give the following table, containing 

 the results of measurements, part of which have already been men- 

 tioned above. 



ff'i 



Ife 



ir' 



in Ohms, in Ohms, i in Ohms. 



in micro- 

 farads. 



Damping- 

 ratio. 



The first five colunms of this table need no nearer explanation; 

 they give the conductive resistances, the capacities and the ^'alues 

 of the time constant 7'. For the values of 2' mentioned the limit 

 of aperiodicity was Just reached. 



The two last columns iiulicate how the string vibrates when the 

 capacity of the condenser and together with it T is zero. In the 

 last colunm but one wc lind the period t expressed in thou.sandths 

 of a second, while the last column gives the damping I'atio /'. The 

 observations have l)een arranged according to the values of 7\ 



Finally some remarks may find a j)lace here on the circumstances 

 under which the condenser method will be useful in [)ractice. For 

 the present the applications \vill presumably be restricted to such 

 measurijig instruments as possess a great internal resistance and a 

 short period of oscillation. A galvanometer for thermo-electric currents 

 with a small internal resistance and a great period of oscillation 

 Avoidd for damping by the condenser metliod recpiire an enormous 

 capacity. The mica or paper condensers, which admit of easy regulat- 

 ion, would be out of the question here, since even the largest sizes 

 of the trade would turn out to be still a hundred thousand times 

 too small. So one would have to have recourse to another kind of 

 condensers, e.g. electrolytic ones, and it would require a separate 

 investigation how fiir these can indeed be rendered practicable for 

 the purpose in view. 



