I ■<) I Official Correspondence on the attacking of 



well applied conductors, we would only now record the concluding 

 paragraph of the latter gentleman's report, as it condenses into a single 

 sentence his sentiments on the question at issue. " In my opinion a 

 good conductor, well connected with the earth, cannot do harm to a 

 building, i. e. though it may induce a discharge on the building, 

 the discharge in itself cannot give rise to any secondary effects which 

 are likely to place the building in more danger than it would have 

 been subject to had the conductor not been there." 



We now proceed to submit to our readers an abstract of Professor 

 Daniell's opinions on the subject before us, as they are detailed in 

 his report on the papers forwarded to him. We feel ourselves con- 

 strained however before entering on this in detail, to notice the most 

 unworthy tone Mr. Daniell has permitted himself to assume in com- 

 menting on Dr. O'Shaughnessy's statements. It is calculated to wound 

 the feelings of those who cannot coincide in opinion with Mr. Daniell, 

 and on the whole appears to us unnecessary in the discussion of a 

 physical question. We can only express our hope, that in any future 

 communication on the subject Mr. Daniell will lay aside that spirit 

 of contempt for his opponent which betrays itself so frequently in 

 the report before us. It is our duty however, in all frankness, to 

 bring to Dr. O'Shaughnessy's notice, that while he has recommended 

 Mr. Daniell to avoid Scylla, he has himself fallen into Charybdis, and 

 has laid himself open to the same censure he has passed upon Mr. 

 Daniell, since his reply to that gentleman's remarks gives evidence 

 of an angry state of feeling, which it would have been well had he 

 subdued. Unseemly personalities degrade science and its votaries 

 much more than those who yield to them are aware of, and we notice 

 them with regret. 



To leave therefore this painful part of our subject, we find that Pro- 

 fessor Daniell is so strongly impressed with the conviction of the pro- 

 tecting power of lightning conductors, that he would rather have them 

 of inferior material, than be without them altogether. He quotes the 

 case of the unprotected Magazine at Dum-Dum, as a proof that Maga- 

 zines without conductors may be blown up by a lightning stroke, while 

 there is no recorded instance of a properly protected building of this 

 description having been struck. Dr. O'Shaughnessy certainly shews that 

 the construction and location of the Magazine at Dum-Dum, were by no 

 means those of a true Magazine, since it was a common square building, 

 having large masses of metal in its vicinity. Such insulation as Dr. 

 O'Shaughnessy claims for a properly constructed Magazine is seldom 

 however, attainable, and we may safely say, that in a Fortress it never is 



