234 Scientific Notices— Miscellaneous. [Maech> 



the private collection of the authors, the immense number of spe- 

 cies contained in the collection, late the property of Mr. George 

 Humphrey, and the free access which the liberality of their 

 friends allows to various other cabinets, will enable them to 

 render the above work by far the most splendid and complete of 

 its kind. 



8. ILlectrical Conducting Poicer of Melted liesmous Bodies. ,.._j 



It is commonly stated, that melted resins become good coti- 

 ductors of electricity and freely allow of its transmission. The 

 following experiments were made with the view of determining 

 to what extent they possess this property. 



i Common resin, shell lac, asphaltum, bees-wax, red and black 

 sealing-wax were melted in separate glass tubes, fitted with 

 wires for taking the electric spark : the)'^ all slowly and with 

 difficulty drew off the charge of a jar, and not with the facility 

 usually supposed. The melted contents of the same tubes 

 acted as non-conductors when made part of the voltaic circuit. 



Several thin glass tubes (previously tried by metallic coatings), 

 were coated outside with copper foil, and about half filled with 

 the melted substances, having wires dipping into them, similar 

 to small leyden phials. The resinous coating, however, distri- 

 buted no charge over the interior of the glass tubes, when con- 

 nected with the machine, which would have been the case with 

 conductors. 



Upon removing the copper coatings and wires, substituting 

 pointed wires bent at right angles, resting against the interior 

 of the glass tube beneath the melted bodies, and suspending 

 them successively from an electrical conductor, placing a metal- 

 lic rod outside opposite the points, sparks passed in all cases per- 

 forating the glass . 



The last cases would indicate that melted resinous bodies are 

 not conductors, and the results obtained in the first instance 

 may possibly be referred to heated air about the apparatus. T.G. 

 — (Journal of Science.) 



9. Lectures on the Ph(vnoniena and Histor)/ of Igneous Meteors 



and Meteorites. 



E. W. Brayley, Jun. ALS., will shortly commence, at the 

 Russel Institution, Great Coram-street, a Course of Lectures on 

 the Phaenomena and History of Igneous Meteors and Meteorites, 

 illustrated by a series of transparent diagrams of Meteors^ an 

 extensive collection of Meteorites, and various experiments in 

 Chemistry and Natural Philosophy. 



