108 Physical Notices of' the Bay of Naples. 



dity for liquids, present the most picturesque movements, for 

 the coiled up fibres uncoil themselves, folded membranes will 

 stretch themselves, and empty vesicles will be filled — effects 

 which cannot take place without motions and agitations. To 

 complete, in short, so many wonders, if we place upon water the 

 molecules of a carbonate, of the debris of shells for example, 

 and add an acid to the liquid, we shall imagine that we have 

 before our eyes a kind of artificial fire-works, and shall see 

 fuses flying in all directions. 



I shall conclude this note by observing, that the discovery 

 of a membrane, which lengthens itself en bo?/au, or into a cy- 

 lindrical mass of the pollen, does not belong to M. Brongniart, as 

 Mr Brown seems to announce, but to our Memoir e sur les tis- 

 sue organiques, as may be shown by merely reading the proces 

 verbal of the meeting of the 21st July 1826, of the Natural 

 History Society, and printed in the Bull, des Sc. Nat. et de Geol. 

 Tom. X. 176, — a paper which is six months anterior to the me- 

 moir quoted by the learned English author. If Mr Brown 

 will have the goodness to repeat our chemical experiments on 

 this subject, he will be convinced that nothing is more cer- 

 tain than the existence of these internal membranes of the 

 pollen. 



Art. XVII. — Physical Notices of the Bay of Naples. Com- 

 municated by the Author. 



No. II. — On the Buried Cities of Herculaneum, Pompeii, and 



Stabice. 



**■ Inde legit Capreas, promontoriumque Minervae 



Et Surrentinos generoso palmite colles, 

 Herculeamque urbem, Stabiasque et in otia natam 



Parthenopen . " 



Ovid. 

 " Hie locus Herculeo nomine clarus erat, 

 Cuncta jacent flammis, et tristi mersa favilla." 



Mart. 



In No. I. of the Physical Notices of the Bay of Naples, we 

 took a rapid view of the most remarkable feature it contains, 

 Mount Vesuvius,— of its topography, phenomena, and produc- 



