THE CHAMBERS LIGHTNING-ROD. 4I 



THE CHAMBERS LIGHTNING-ROD. 



Note on an Article in Volume III. of the Proceedings of the Davenport 

 Academy of Sciences. 



BY E. W. CLAYPOLE. 

 Presented before the Davenport Academy of Sciences, October 26th, 18S3. 



In the second part of the third vohime of the proceedings of the 

 Davenport Academy, is a short paper by W. H. Pratt, entitled "The 

 Chambers Rod and the Phoenix Mill Fire." In that paper it seems to 

 me that Prof Pratt has satisfactorily proved that the fire in the^iill was 

 caused by lightning. The fact that the mill was clean, and had not 

 been running for some weeks, is sufficient to meet the allegation that 

 the fire may have been caused by spontaneous combustion, aided by 

 explosive dust. It might have been added, that there was no explo- 

 sion. Moreover, one man bore distinct testimony to having seen the 

 lightning strike the mill. 



The mill, it appears, was fitted with the "Chambers" rod, the pecu- 

 liarity of which is that it has no ground connection, and professes to 

 dissipate the electric charge without conveying it to the earth. Much 

 discussion has been aroused in regard to the protective power of this 

 mode of constructing and setting up lightning-rods. Experience, which 

 should be the final court of appeal, is not, in this case, so conclusive as 

 it might be. Tightning-rods of all kinds are so carelessly put up, and, 

 what is more, so carelessly kept up, that accidents from lightning are 

 not infrequent even to "protected" buildings. That well-made and 

 well-kept lightning-rods are,, however, not only efficacious, but thor- 

 oughly effective, in preventing damage, is proved by the fact that no 

 loss has been sustained by the British navy from this cause since the 

 adoption of Sir W. Snow Harris's lightning conductors. It should be 

 borne in mind that a rod does not avert the electric discharge, but only 

 the danger and damage that would be caused by an electric explosion. 

 Ships of the British navy are probably struck as often now as formerly, 

 but no explosion ensues, and no mischief is done. Yet, in spite of all 

 the "protection" afforded by lightning-rods in this country, in some 



[Proc. D, a. N. S., Vol. IV.] 6 [March 13, 1884.] 



