1893.] 



The Electrolysis of Steam. 



97 



On trying to use the coil in the ordinary way, the current obtained 

 was exceedingly small, so small that the hydrogen liberated in a water 

 voltameter placed in series with the discharge tube only amounted 

 to abont 0*25 c.c. per hour. As it is inconvenient to work with such 

 small currents, on account of the time which has to elapse before a 

 quantity of gas can be obtained sufficient to enable accurate measure- 

 ments to be taken, I endeavoured to increase the current from the 

 coil. I found that, as I believe is the case with all induction coils, the 

 condenser supplied with it had not nearly enough capacity to enable 

 the coil to give out its maximum current. When I added to this 

 condenser a large paraffin paper one, with a capacity of about 

 6 micro-farads, the current from the coil was increased more than 

 twenty times, and I found no difficulty in getting from 4 to 6 c.c. of 

 hydrogen liberated per hour in the water voltameter in series with 

 the discharge tube. 



In order to measure the quantity of electricity which passes through 

 the spark tube, a well-insulated water voltameter was placed in series 

 with it, and the quantity of hydrogen liberated in this voltameter 

 observed. The gases liberated in this voltameter were repeatedly 

 tested, in order to see whether there was any mixing up of the 

 hydrogen and oxygen in the collecting tubes over its electrodes. 

 Such admixture seemed possible, as the electromotive force produced 

 when the circuit is " made "is in the opposite direction to that pro- 

 duced when it is broken. The test consisted in vigorously sparking 

 through the gases collected in the voltameter, but no contraction 

 occurred. As, however, it is very difficult to get a mixture of hydro- 

 gen and oxygen to explode if the hydrogen is greatly in excess, I 

 added to the hydrogen in the voltameter enough oxygen to cause an 

 explosion ; the contraction in this case corresponded to the oxygen 

 added, showing that there was no oxygen originally present. We 

 may therefore conclude that the current sent through the secondary 

 circuit on " making" the coil is in this case too small, in comparison 

 with that produced on " breaking " the circuit, for its effects to be 

 appreciable. 



Method of Making the Experiments. 



After it had been ascertained, in the way previously described, that 

 all the air had been expelled from, the vessel, the eudiometer tubes 

 were filled with mercury and placed over the ends of the delivery 

 tubes, and the spark tube connected up with the coil. 



The next step was to see if the rates of flow through the delivery 

 tubes were approximately equal. This was done by turning on the 

 coil and collecting the mixed gases in the eudiometer tubes ; if the 

 volume of these gases in the two tubes was not the same, the appa- 



VOL. LIU. H 



