Mr Murray on the Paragrele or Protector from Hail. 103 



feet, the body of warmer air must be collected into a strange pyramidal form, 

 which one would think the cold circumambient air would soon pull down. 



Leith, / 

 215/ April 1827. V 



On the Paragrele or Protector from Hail. By John Mueray, 

 Esq. F. L. S., M. W. S., &c. Communicated by the Author. 



Dear Sir, 



Jr ERMiT me to submit to your notice a few remarks on the 

 subject oi paragreles, as I have witnessed them extensively used 

 in some districts abroad. 



The term implies that they are safeguards from hail, as para- 

 tonneres signify protectors from the thunder-storm ; they both 

 depend on similar principles, and must stand or fall together. 

 Conductors of lightning, if constructed on scientific principles, 

 have been found an efficient guard from meteoric fire ; and hail, 

 being a meteorological phenomenon dependent on, and modified 

 by, the electricity of the atmosphere, it follows, that paragreles 

 are founded on the true principles of inductive science, and must 

 form a shield of protection to the property of those enlightened 

 individuals whose intelligence may lead them to their adoption. 

 Superstition, pale and terrified, may regard their erection as op- 

 posed to the providence of Heaven, and ignorance erect its crest 

 of feeble opposition ; but Truth defies their combined attack, and 

 triumphs in the light she diffuses. If an insulated thunder-rod 

 can discharge the cloud of its forked and fiery elements, and 

 scatter its parts to the four winds of heaven, a fortiori paragreles, 

 or pointed metallic wires, infinitely multiplied, and extending 

 over a vast surface, must exercise a power infinitely greater. 



I consider it quite absurd to circumscribe the influence of a 

 conducting rod within a given radius, as some have done ; and 

 have confined it to about 300 feet, because all this must depend 

 on a variety of combining circumstances, — as the comparative de- 

 gree of the conducting character of the metallic tod, the mete- 

 orological feature of the ah', as to its barometric or hygrome- 

 tric state : the intensity and altitude of the cloud, and the elec- 



