16 THE LATE MR. WILLIAM STURGEON ON 



answered even any of the purposes for which they were 

 first introduced, the first flash of lightning that any of them 

 received would destroy it. Such an accident on board of 

 ship might be but of little consequence, because the vane- 

 spindle being accessible could easily be pointed anew; but 

 a similar accident to the conductor of a tall factory chimney, 

 would entail a heavy expense in scaffolding, &c, before the 

 top of the conductor could be arrived at; so that the sup- 

 posed virtues of points is an expensive treasure, in continual 

 jeopardy. Moreover, as there has never yet been an instance 

 known of pointed conductors abating the violence of light- 

 ning discharges, there is not an attribute belonging to them, 

 nor a recorded circumstance in their favour, that can justify 

 a continuance of their employment in preference to conductors 

 of other forms at their superior extremities ; whilst the grave 

 charge of their being instrumental in facilitating strokes of 

 lightning, almost imperatively demands their immediate and 

 total discontinuance. 



86. Notwithstanding the attempts that have been made to 

 propagate the idea that balls, surmounting conductors, are 

 virtually points, when compared to the immense surface 'of 

 a thunder-cloud, and (by inference) act in a similar manner, 

 the result of Franklin's experiment with the point and head 

 of a pin alternately presented to the prime conductor of his 

 machine would, independently of any other fact, be sufficient 

 to show the fallacy of the hypothesis. But the inaptitude of 

 polished bails in drawing off the electric fluid from vicinal 

 bodies, or intromitting it from the air, is a fact too well 

 established at the present day to admit of either equivocation 

 or doubt. Hence such terminations to conductors are in- 

 capable of qualifying the air beneath a thunder-cloud for the 

 transmission of lightning; and consequently have no power 

 in predisposing the locality for its reception. These negative 

 qualifications, in connection with the certainty of their with- 



