489 



Official Correspondence on the attaching of Lightning Con- 

 ductors to Powder Magazines. 



[From a Correspondent.] 

 II. 



It has afforded us much pleasure to find that our remarks 

 on the Conductor question, published in the last number of 

 this Journal, have been so generally, we might almost say 

 universally, assented to ; and we return to the subject for the 

 purpose of noticing briefly the reply Dr. O'Shaughnessy has 

 published to certain passages of our paper, and also of sub- 

 stantiating more fully some of the statements we therein 

 ventured to make. 



A regard for the simple courtesies of science, were there 

 no higher actuating motive, would induce us to pass over 

 in silence Dr. O'Shaughnessy's misrepresentations of our 

 intentions in taking the part we have done in this discussion, 

 and we the more readily follow this course, as we are well 

 assured that unprejudiced readers have attempted in vain to 

 discover in our paper the grounds of his complaint. "We 

 may however remark, that when any scientific man comes 

 forward and lays before the public, statements which are in- 

 tended to furnish materials for some important generalisation, 

 he ought to be prepared to submit them to the most care- 

 ful and rigid scrutiny, and he has no right to feel offended 

 if others demand an amount of evidence for their substanti- 

 ation greater than that which has satisfied his own mind. 

 An immunity from this process of verification would only be 

 productive of unmixed evil to science, and it consequently 

 never has been, nor ever will be, accorded to any one, how- 

 ever high may be our confidence in his habits of careful 

 observation, or strict honesty of scientific character. 



We have no hesitation whatever in acknowledging that 

 the detection of one important error of measurement in Dr. 

 O'Shaughnessy's papers shook our confidence in the other 



