On certain P/uenomena of Electrical Discharge. 137 



produce twice the effect ; whereas the effect is unchanged. Then 

 again I am informed that my paper is full of errors, that without 

 the necessary knowledge, I have deduced results unintelligible 

 both to Dr. lliess and others, and he is " not aware that any one, 

 either here or in England, had found these results more intel- 

 ligible than he had done." All these things are very easily said ; 

 but here is an extract from Far aday^s Researches, 12th series, 1363 : 

 ^' Many philosophers have examined the circumstances of this 

 limiting action in air, but as far as 1 know none have come near 

 Mr. Harris as to the accuracy with, and the extent to, which he 

 has carried on his investigations.^^ This, be it remembered, 

 refers to the particular method of research so pointedly objected 

 to by M. Riess, " if his memory is correct.-'^ That my researches 

 may be ill understood by Dr. Ricss is possible, and yet that 

 may not be altogether my fault ; it may equally arise from some 

 source of misapprehension by him. We have an instance of this 

 in his late notice of my memoir, in his remark relative to the 

 resistance to discharge as depending on the transfer of the accu- 

 mulation from the glass to its coating, and the accumulation of 

 a given quantity of electricity upon an increased number of jars. 

 These sources of resistance are evidently new to Dr. Riess, and 

 so far as I can see, have never entered into his calculation ; now 

 / have " ascertained by experiment " the fallacy of the significa- 

 tion which Dr. Riess attaches to his symbol, as seen in my former 

 communication. 



Again, Dr. Riess observes, " It is not true that I ascribed the 

 unsuccessful experiments of Sir W. Harris to the faulty arrange- 

 ment of his thermometer." I think it will be allowed, that before 

 employing so strong an expression, somethmg like certainty upon 

 the point in question should have been established. Well ! here 

 is an extract from Dr. Riess^s paper {Annates de Chimie for 1838, 

 tome Ixix. p. 116) : " Ilfaut attribuer a la construction imparfaite 

 du thermometre, que les experiences de M. Harris sont restees in- 

 fructueuses ; " and yet I am told that it is " not true" that M. 

 Riess had referred what he calls my unsuccessful experiments to 

 the imperfection of my instrument*. 



Nothing that Dr. Riess has advanced relative to Kinnersley^s 

 thermometer, with the whole detail of which I have been long 

 familiar, at all serves to convince me that my instrument in 

 all its generality was not an entirely new instrument at the 

 time it was first produced, at least so far as it is possible to 

 produce a perfectly new instrument ; and I again repeat, that 

 the main object of all the primitive air-electrometers, was the 

 explosive violence of the electrical discharge in a confined space 

 of air, Kinnersley's casual introduction of various substances 

 m^oii # gee also De la Riye, Traits de VEUctridte, vol. ii. p. 154. 



