108 Mr. H. M. Yernon on the 



roughly, 1000, and the effective pressure of the oscillatory 

 component 6000 volts. This would give 72 amperes, and the 

 " skin effect " would absorb a great deal of power. 



There is, however, a simpler explanation. The cables have 

 considerable capacity, and take an appreciable current. This 

 " leads " relatively to the electromotive force, so the capacity 

 current passes in the armature-coils when they are just in the 

 position to magnetize the fields more strongly. The fields 

 cannot follow each pulsation of excitation so produced, but are 

 affected by it. Their average excitation is increased. I have 

 tried putting a condenser on one of the old Gramme alterna- 

 tors, which have rather weak fields, and a large number of 

 armature ampere turns. The pressure ran up and burned the 

 voltmeter. I have already gone fully into the action of lead- 

 ing and lagging currents on dynamo fields elsewhere, so the 

 subject need not be pursued here. It would, no doubt, be 

 possible to make an alternator excite itself like a series 

 machine by putting a condenser on the terminals instead of 

 exciting the fields by a direct current machine. Such an 

 arrangement seems scarcely commercial, though interesting. 



XIII. On the so-called Meta-Elements. 

 By H. M. Yernon, Scholar of Merton College, Oxford*. 



DURING the last few years we have had brought before 

 us by several eminent chemists, chief among whom may 

 be mentioned Prof. Crookes and M. Lecoq de Boisbaudran, 

 views on the nature of elements totally different from any 

 that had before existed in the minds of chemists. These 

 views being so totally different from anything proposed before, 

 were at first received incredulously, and it is only quite 

 recently that at all a large number of chemists have put faith 

 in them. Even as it is, we may, I think, say that belief in 

 what is referred to, namely the so-called meta-elements, is 

 extremely qualified. The existence of these bodies seems to 

 be so much at variance with the known laws of Chemistry, 

 and especially with that which is known as the Periodic Law, 

 that, though positive proof of their existence would seem to be 

 forthcoming, yet it will probably need much more proof than 

 has at present been advanced to render the belief in their 

 existence universal. 



The question now comes, whether these "proofs" of the 

 existence of meta-elements are in reality proofs, or whether 



* Communicated by the Author. 



