Intelligence and Miscellaneous Articles. 75 



like a rocket throwing off numerous corruscations of intense light; 

 but without any report or noise of any kind. Its apparent eleva- 

 tion inconsiderable. 



Another beautiful Meteor observed at the same Village on the 20tk of 

 May, 1832. 

 At 6 hours 40 minutes p.m. a large pear-shaped meteor was ob- 

 served shooting very rapidly in a horizontal position, and in a direc. 

 tion from north to south. Nothing could exceed the brilliant mix- 

 ture of green, tinged with blue colours, exhibited during its rapid 

 progress. It left a luminous train of great length behind, and re- 

 mained visible about three seconds, then disappeared in the southern 

 horizon, without exhibiting any signs of exploding. 



ANALYSIS OF PLOMBGOMJIE. BY M. DUFRESNOY. 

 The compound of oxide of lead and alumina, called by mineralo- 

 gists plombgomme, on account of its resemblance to drops of gum 

 which exude from trees, has hitherto been found only in Huelgoat 

 mine in Brittany. It has, however, lately occurred in a lead mine 

 near Beaujeu : it is found in small mammillated masses, with slightly 

 varying textures ; some are of a yellowish white colour, externally 

 very shining, and the fracture is both splintery and testaceous, with- 

 out any trace of crystallization ; others are slightly greenish, com- 

 posed of concentric layers, and possess a radiated structure like 

 wavellite. When observed with a microscope, the fibres appear to be 

 crystalline, with a rhombic fracture, like some arragonites. 



The hardness of plombgomme is intermediate as to that of carbo- 

 nate and phosphate of lime. Its specific gravity is 4*88 : before the 

 blowpipe it decrepitates ; on charcoal it swells and yields a scoria- 

 ceous white enamel. 

 By analysis it yielded 



Silica 2-11 



Alumina 34-23 



Deutoxide of lead 43"42 



Phosphoric acid I -SO 



Water 16-14 



Loss 2.21 



100-00 



The specimen subjected to analysis contained phosphate of lead: 

 it is very probable that the phosphoric acid found indicates a certain 

 quantity of phosphate of lead mixed with the plombgomme. On this 

 supposition, the analysis should be thus stated : 



Silica 2-11 



Alumina 34-23 



Deutoxide of lead 37-5 1 



Phosphate of lead 7-80 



Water 16-14 



Loss 2-21 



0.0 10 



Ann. de Chim. et de Phys., tome lix. p. 440. 



