1818.] Scientific Intelligence. 393 



which are to be seen on the mollusca are larger, but less bright. 

 But that luminous appearance, which diffuses itself over the 

 whole surface of the sea, arises from a dissolved slimy matter, 

 which spreads its light like that proceeding from phosphorus. 

 The most minute glittering particles, when highly magnified, had 

 the appearance of small and solid spherical bodies." 



IX. Paris Aerolite. 



We are informed in the Journ. de Physique for January, p. 30, 

 that the account of an aerolite, reported to have fallen in Paris, 

 which we noticed in our number of the Annals for December 

 last, is entirely without foundation. 



X. On the Fusion of Silica. By Joshua Mantell, Esq. 



(To the Editors of the Annals of Philosophy.) 

 GENTLEMEN, Lewes, April 10, 1818. 



If the following account of some experiments on the fusion of 

 silica, by means of the oxyhydrogen blow-pipe, should appear to 

 merit a place in the Annals of Philosophy, I shall feel much 

 obliged by its early insertion. With a view to ascertain if the 

 purity of the gases and the intensity of the temperature were 

 sufficient to produce the same metallic appearance in the expe- 

 riments described in the letter inserted in your last journal, pure 

 silicftj mixed with common lamp oil, was exposed to the action 

 of the ignited gases ; at the instant of its fusion the mass was 

 removed, and exhibited several globules of a metallic appear- 

 ance^ and of a splendid silvery lustre ; the result of this experi- 

 ment having proved satisfactory, animal oil, intimately blended 

 with finely pulverized charcoal, was submitted to the action of 

 the oxyhydrogen blow-pipe, that it might be determined how far 

 the metallic substance, produced in the preceding experiment, 

 was caused by the charcoal contained in the animal oil, accord- 

 ing to the suggestion of Dr. Thomson ; the oil was immediately 

 dissipated, but not the least particle of a metallic nature could 

 be discovered on the charcoal that was used as a support. Car- 

 bonate oflime, filiate of lime, carbonate of magnesia, &c. mixed 

 with oil, were severally exposed in a similar manner, and afforded 

 similar results. As in every instance the same degree of heat 

 was applied, and the same precautions observed, may we not 

 infer that the metallic lustre, apparent in the first experiment, is 

 not to be attributed to the charcoal contained in the animal oil, 

 but is occasioned by the reduction of the earth to its metallic 

 state. Impressed with this idea, pure silica, placed in a charcoal 

 crucible, was brought to the action of the gaseous stream ; but 

 it was instantly scattered by the blast in every direction, and the 

 experiment was necessarily abandoned. To prevent a similar 

 inconvenience, the silica was moistened with water and was 

 instantly fused into a white transparent vitreous substance; but 



