404 Miscellaneous Intelligence. 



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

 for talcing the electric spark : they all slowly and with difficulty 

 drew ofi the charge of a jar, and not with the facility usually sup- 

 posed. The melted contents of the same tubes acted as non-con- 

 ductors, 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 vials. The resinous coating, however, distributed no charge 

 over the interior of the glass tubes, when connected with the ma- 

 chine, which would have been tlie 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 suc- 

 cessively from an electrified conductor, placing a metallic rod out- 

 side opposite the points, sparks passed in all cases perforating 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. 



III. Natural Histoky. 



1. Volcano of Ptirace — River containing free Acids. — The follow- 

 ing short abstract is from an important paper by M. Humboldt on 

 the Volcano of Purace, its geognostical relations and peculiar 

 features. A river issues from it, which contains enough free mu- 

 riatic and sulphuric acids, to render it slightly acid to the taste, 

 from which circumstance it has received the name of Vinegar 

 River from the inhabitants. The two volcanoes of Purac6 and 

 Sotara form part of the central chain of the Andes of new Grenada. 

 Part of the way up the mountain, there is a small plain and a village, 

 inhabited by some poor Indians who cultivate the ground. The 

 village is named after the mountain and stands upon the edge of 

 precipices, amongst which runs the river Pusambio or Vinegar 

 River, forming three beautiful cascades. This river commences at 

 a height of 1700 toises issuing from a very inaccessible place, and 

 though at the lower cascades, it is not of a temperature above that 

 of the atmosphere, yet, M. Humboldt has no doubt that its 

 sources are very hot. The same thing is asserted also by the in- 

 habitants of the place, and the traveller himself saw a column of 

 smoke rise from the spot. 



The waters are so injurious from the presence of the acids in 

 them, as to destroy the fish in the river Cauca to some distance 

 (four leagues) from the place where they first enter it : and it was 

 found also, that persons who remain some time in the neighbour- 



